diff --git a/README.md b/README.md
index 8d7e8aee..e2da9c64 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,34 @@
-# java-baseball-precourse
\ No newline at end of file
+# java-baseball-precourse
+
+### 문제
+- 기본적으로 1부터 9까지 서로 다른 수로 이루어진 3자리의 수를 맞추는 게임이다.
+- 같은 수가 같은 자리에 있으면 스트라이크, 다른 자리에 있으면 볼, 같은 수가 전혀 없으면 포볼 또는 낫싱이란 힌트를
+얻고, 그 힌트를 이용해서 먼저 상대방(컴퓨터)의 수를 맞추면 승리한다.
+  - [예] 상대방(컴퓨터)의 수가 425일 때, 123을 제시한 경우 : 1스트라이크, 456을 제시한 경우 : 1스트라이크 1볼,
+  789를 제시한 경우 : 낫싱
+- 위 숫자 야구게임에서 상대방의 역할을 컴퓨터가 한다. 컴퓨터는 1에서 9까지 서로 다른 임의의 수 3개를 선택한다. 게임 플레이어는 컴퓨터가 생각하고 있는 3개의 숫자를 입력하고, 컴퓨터는 입력한 숫자에 대한 결과를 출력한다.
+- 이 같은 과정을 반복해 컴퓨터가 선택한 3개의 숫자를 모두 맞히면 게임이 종료된다.
+- 게임을 종료한 후 게임을 다시 시작하거나 완전히 종료할 수 있다.
+- 사용자가 잘못된 값을 입력할 경우 [ERROR]로 시작하는 에러 메시지를 출력하고 게임을 계속 진행할 수 있어야
+
+### 구조
+- 입력기 (controller)
+- 출력기 (view)
+- baseball 판독기 (model)
+- baseball 정답 생성기 (model)
+- baseball 게임 진행 (model)
+- 에러 핸들러
+
+### 기능 요구사항
+- [X] baseball 정답 생성
+  - [X] 1부터 9까지의 다른 수로 이루어진 3자리의 수를 생성합니다.
+    - 제약 사항: 1부터 9까지만, 정답 길이 3
+- [X] baseball 정답 판독
+  - [X] 정답과 비교해서 자리와 숫자가 모두 같은 경우 strike의 카운트를 반환합니다.
+  - [X] 정답과 비교해서 숫자만 같고 자리만 같을 경우 ball 의 카운트를 올립니다.
+- [X] baseball 게임 진행
+  - [X] 게임이 시작된 상황이라면 숫자를 입력 받고 판독 결과를 반환합니다.
+  - [X] 게임이 진행중이 아니라면 1의 입력의 경우 정답 생성을 요청하고, 숫자 입력을 요구합니다.
+  - [X] 게임이 진행중이 아니라면 2의 입력의 경우 게임을 종료합니다.
+- [X] 입력기
+- [X] 출력기
diff --git a/src/main/java/Main.java b/src/main/java/Main.java
new file mode 100644
index 00000000..35200557
--- /dev/null
+++ b/src/main/java/Main.java
@@ -0,0 +1,10 @@
+import config.GameConfig;
+import controller.GameController;
+
+public class Main {
+
+    public static void main(String[] args) {
+        GameController gameController = new GameConfig().gameController();
+        gameController.run();
+    }
+}
diff --git a/src/main/java/config/GameConfig.java b/src/main/java/config/GameConfig.java
new file mode 100644
index 00000000..16a2feb8
--- /dev/null
+++ b/src/main/java/config/GameConfig.java
@@ -0,0 +1,27 @@
+package config;
+
+import controller.GameController;
+import model.BaseballAnswerGenerator;
+import model.BaseballAnswerJudge;
+import model.BaseballGameManager;
+import model.BaseballInputValidator;
+import view.OutputView;
+
+public class GameConfig {
+
+    public GameController gameController() {
+        return new GameController(
+                gameManager(),
+                new BaseballInputValidator(),
+                new OutputView()
+        );
+    }
+
+    private BaseballGameManager gameManager() {
+        return new BaseballGameManager(
+                new BaseballAnswerGenerator(),
+                new BaseballAnswerJudge()
+        );
+    }
+
+}
diff --git a/src/main/java/constant/GameConstants.java b/src/main/java/constant/GameConstants.java
new file mode 100644
index 00000000..ec10db91
--- /dev/null
+++ b/src/main/java/constant/GameConstants.java
@@ -0,0 +1,9 @@
+package constant;
+
+public class GameConstants {
+    public static final int ANSWER_LENGTH = 3;
+    public static final int MIN_DIGIT = 1;
+    public static final int MAX_DIGIT = 9;
+    public static final char EXCLUDED_DIGIT = '0';
+    public static final String RESTART_COMMAND = "1";
+}
diff --git a/src/main/java/constant/GameMessages.java b/src/main/java/constant/GameMessages.java
new file mode 100644
index 00000000..078df844
--- /dev/null
+++ b/src/main/java/constant/GameMessages.java
@@ -0,0 +1,16 @@
+package constant;
+
+public class GameMessages {
+    public static final String GAME_START = "숫자 야구 게임을 시작합니다.";
+    public static final String INPUT_PROMPT = "숫자를 입력해주세요 : ";
+    public static final String NOTHING = "낫싱";
+    public static final String BALL = "볼";
+    public static final String STRIKE = "스트라이크";
+    public static final String GAME_WON = "3개의 숫자를 모두 맞히셨습니다! 게임 종료";
+    public static final String RESTART_PROMPT = "게임을 새로 시작하려면 1, 종료하려면 2를 입력하세요.";
+
+    public static final String ERROR_INVALID_LENGTH = "[ERROR] 3자리 숫자를 입력해주세요.";
+    public static final String ERROR_NOT_DIGIT = "[ERROR] 숫자만 입력해주세요.";
+    public static final String ERROR_INVALID_RANGE = "[ERROR] 1부터 9까지의 숫자만 입력해주세요.";
+    public static final String ERROR_DUPLICATE = "[ERROR] 중복되지 않는 숫자를 입력해주세요.";
+}
diff --git a/src/main/java/controller/GameController.java b/src/main/java/controller/GameController.java
new file mode 100644
index 00000000..858ac58c
--- /dev/null
+++ b/src/main/java/controller/GameController.java
@@ -0,0 +1,57 @@
+package controller;
+
+import constant.GameConstants;
+import model.GameManager;
+import model.InputValidator;
+import view.OutputView;
+
+import java.util.Scanner;
+
+public class GameController {
+
+    private final GameManager gameManager;
+    private final InputValidator inputValidator;
+    private final OutputView outputView;
+    private final Scanner scanner;
+
+    public GameController(GameManager gameManager, InputValidator inputValidator, OutputView outputView) {
+        this.gameManager = gameManager;
+        this.inputValidator = inputValidator;
+        this.outputView = outputView;
+        this.scanner = new Scanner(System.in);
+    }
+
+    public void run() {
+        outputView.printGameStart();
+        while (true) {
+            playGame();
+            if (!askRestart()) break;
+        }
+    }
+
+    private void playGame() {
+        gameManager.startGame();
+        while (gameManager.isPlaying()) {
+            outputView.printInputPrompt();
+            String input = scanner.nextLine();
+            processGuess(input);
+        }
+        outputView.printGameWon();
+    }
+
+    private void processGuess(String input) {
+        try {
+            inputValidator.validate(input);
+            int[] result = gameManager.guess(input);
+            outputView.printResult(result[0], result[1]);
+        } catch (IllegalArgumentException e) {
+            outputView.printError(e.getMessage());
+        }
+    }
+
+    private boolean askRestart() {
+        outputView.printRestartPrompt();
+        String input = scanner.nextLine();
+        return input.equals(GameConstants.RESTART_COMMAND);
+    }
+}
diff --git a/src/main/java/model/AnswerGenerator.java b/src/main/java/model/AnswerGenerator.java
new file mode 100644
index 00000000..f48f03b0
--- /dev/null
+++ b/src/main/java/model/AnswerGenerator.java
@@ -0,0 +1,7 @@
+package model;
+
+public interface AnswerGenerator {
+
+    String generateAnswer();
+
+}
diff --git a/src/main/java/model/AnswerJudge.java b/src/main/java/model/AnswerJudge.java
new file mode 100644
index 00000000..1cb4941d
--- /dev/null
+++ b/src/main/java/model/AnswerJudge.java
@@ -0,0 +1,8 @@
+package model;
+
+public interface AnswerJudge {
+
+    Integer countStrikes(String input, String answer);
+
+    Integer countBalls(String input, String answer);
+}
diff --git a/src/main/java/model/BaseballAnswerGenerator.java b/src/main/java/model/BaseballAnswerGenerator.java
new file mode 100644
index 00000000..b56bce45
--- /dev/null
+++ b/src/main/java/model/BaseballAnswerGenerator.java
@@ -0,0 +1,29 @@
+package model;
+
+import constant.GameConstants;
+
+import java.util.HashSet;
+import java.util.Set;
+import java.util.concurrent.ThreadLocalRandom;
+
+public class BaseballAnswerGenerator implements AnswerGenerator {
+
+    @Override
+    public String generateAnswer() {
+        Set<Integer> numbers = new HashSet<>();
+
+        while (numbers.size() < GameConstants.ANSWER_LENGTH) {
+            numbers.add(ThreadLocalRandom.current().nextInt(
+                    GameConstants.MIN_DIGIT,
+                    GameConstants.MAX_DIGIT + 1
+            ));
+        }
+
+        StringBuilder answer = new StringBuilder();
+        for (int n : numbers) {
+            answer.append(n);
+        }
+
+        return answer.toString();
+    }
+}
diff --git a/src/main/java/model/BaseballAnswerJudge.java b/src/main/java/model/BaseballAnswerJudge.java
new file mode 100644
index 00000000..b280c985
--- /dev/null
+++ b/src/main/java/model/BaseballAnswerJudge.java
@@ -0,0 +1,29 @@
+package model;
+
+import constant.GameConstants;
+
+public class BaseballAnswerJudge implements AnswerJudge {
+
+    @Override
+    public Integer countStrikes(String input, String answer) {
+        int result = 0;
+        for (int index = 0; index < GameConstants.ANSWER_LENGTH; index++) {
+            if (input.charAt(index) == answer.charAt(index)) {
+                result++;
+            }
+        }
+        return result;
+    }
+
+    @Override
+    public Integer countBalls(String input, String answer) {
+        int result = 0;
+        for (int index = 0; index < GameConstants.ANSWER_LENGTH; index++) {
+            char item = input.charAt(index);
+            if (item != answer.charAt(index) && answer.indexOf(item) != -1) {
+                result++;
+            }
+        }
+        return result;
+    }
+}
diff --git a/src/main/java/model/BaseballGameManager.java b/src/main/java/model/BaseballGameManager.java
new file mode 100644
index 00000000..06ac6a25
--- /dev/null
+++ b/src/main/java/model/BaseballGameManager.java
@@ -0,0 +1,48 @@
+package model;
+
+import constant.GameConstants;
+
+public class BaseballGameManager implements GameManager {
+    private final AnswerGenerator answerGenerator;
+    private final AnswerJudge answerJudge;
+    private String answer;
+    private boolean playing;
+    private boolean gameWon;
+
+    public BaseballGameManager(AnswerGenerator answerGenerator, AnswerJudge answerJudge) {
+        this.answerGenerator = answerGenerator;
+        this.answerJudge = answerJudge;
+        this.playing = false;
+        this.gameWon = false;
+    }
+
+    @Override
+    public void startGame() {
+        this.answer = answerGenerator.generateAnswer();
+        this.playing = true;
+        this.gameWon = false;
+    }
+
+    @Override
+    public int[] guess(String input) {
+        int strikes = answerJudge.countStrikes(input, answer);
+        int balls = answerJudge.countBalls(input, answer);
+
+        if (strikes == GameConstants.ANSWER_LENGTH) {
+            this.playing = false;
+            this.gameWon = true;
+        }
+
+        return new int[]{strikes, balls};
+    }
+
+    @Override
+    public boolean isPlaying() {
+        return playing;
+    }
+
+    @Override
+    public boolean isGameWon() {
+        return gameWon;
+    }
+}
diff --git a/src/main/java/model/BaseballInputValidator.java b/src/main/java/model/BaseballInputValidator.java
new file mode 100644
index 00000000..4b1d3a1c
--- /dev/null
+++ b/src/main/java/model/BaseballInputValidator.java
@@ -0,0 +1,49 @@
+package model;
+
+import constant.GameConstants;
+import constant.GameMessages;
+
+import java.util.HashSet;
+import java.util.Set;
+
+public class BaseballInputValidator implements InputValidator {
+
+    @Override
+    public void validate(String input) {
+        validateLength(input);
+        validateDigitsOnly(input);
+        validateRange(input);
+        validateNoDuplicates(input);
+    }
+
+    private void validateLength(String input) {
+        if (input.length() != GameConstants.ANSWER_LENGTH) {
+            throw new IllegalArgumentException(GameMessages.ERROR_INVALID_LENGTH);
+        }
+    }
+
+    private void validateDigitsOnly(String input) {
+        for (char c : input.toCharArray()) {
+            if (!Character.isDigit(c)) {
+                throw new IllegalArgumentException(GameMessages.ERROR_NOT_DIGIT);
+            }
+        }
+    }
+
+    private void validateRange(String input) {
+        for (char c : input.toCharArray()) {
+            if (c == GameConstants.EXCLUDED_DIGIT) {
+                throw new IllegalArgumentException(GameMessages.ERROR_INVALID_RANGE);
+            }
+        }
+    }
+
+    private void validateNoDuplicates(String input) {
+        Set<Character> seen = new HashSet<>();
+        for (char c : input.toCharArray()) {
+            if (!seen.add(c)) {
+                throw new IllegalArgumentException(GameMessages.ERROR_DUPLICATE);
+            }
+        }
+    }
+}
diff --git a/src/main/java/model/GameManager.java b/src/main/java/model/GameManager.java
new file mode 100644
index 00000000..054db87f
--- /dev/null
+++ b/src/main/java/model/GameManager.java
@@ -0,0 +1,13 @@
+package model;
+
+public interface GameManager {
+
+    void startGame();
+
+    int[] guess(String input);
+
+    boolean isPlaying();
+
+    boolean isGameWon();
+
+}
diff --git a/src/main/java/model/InputValidator.java b/src/main/java/model/InputValidator.java
new file mode 100644
index 00000000..8715129d
--- /dev/null
+++ b/src/main/java/model/InputValidator.java
@@ -0,0 +1,7 @@
+package model;
+
+public interface InputValidator {
+
+    void validate(String input);
+
+}
diff --git a/src/main/java/view/OutputView.java b/src/main/java/view/OutputView.java
new file mode 100644
index 00000000..4d48c225
--- /dev/null
+++ b/src/main/java/view/OutputView.java
@@ -0,0 +1,42 @@
+package view;
+
+import constant.GameMessages;
+
+public class OutputView {
+
+    public void printGameStart() {
+        System.out.println(GameMessages.GAME_START);
+    }
+
+    public void printInputPrompt() {
+        System.out.print(GameMessages.INPUT_PROMPT);
+    }
+
+    public void printResult(int strikes, int balls) {
+        if (strikes == 0 && balls == 0) {
+            System.out.println(GameMessages.NOTHING);
+            return;
+        }
+
+        StringBuilder result = new StringBuilder();
+        if (balls > 0) {
+            result.append(balls).append(GameMessages.BALL).append(" ");
+        }
+        if (strikes > 0) {
+            result.append(strikes).append(GameMessages.STRIKE);
+        }
+        System.out.println(result.toString().trim());
+    }
+
+    public void printGameWon() {
+        System.out.println(GameMessages.GAME_WON);
+    }
+
+    public void printRestartPrompt() {
+        System.out.println(GameMessages.RESTART_PROMPT);
+    }
+
+    public void printError(String message) {
+        System.out.println(message);
+    }
+}
diff --git a/src/test/java/BaseballAnswerGeneratorTest.java b/src/test/java/BaseballAnswerGeneratorTest.java
new file mode 100644
index 00000000..f1fe8e33
--- /dev/null
+++ b/src/test/java/BaseballAnswerGeneratorTest.java
@@ -0,0 +1,46 @@
+import model.AnswerGenerator;
+import model.BaseballAnswerGenerator;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class BaseballAnswerGeneratorTest {
+
+    private AnswerGenerator answerGenerator;
+
+    @BeforeEach
+    void setup() {
+        answerGenerator = new BaseballAnswerGenerator();
+    }
+
+    @DisplayName("정답은 3자리 숫자이다")
+    @Test
+    void generateAnswer_returnsLengthThree() {
+        String answer = answerGenerator.generateAnswer();
+        assertThat(answer.length()).isEqualTo(3);
+    }
+
+    @DisplayName("정답은 0을 포함하지 않는다")
+    @Test
+    void generateAnswer_doesNotContainZero() {
+        String answer = answerGenerator.generateAnswer();
+        assertThat(answer).doesNotContain("0");
+    }
+
+    @DisplayName("정답은 숫자로만 이루어져 있다")
+    @Test
+    void generateAnswer_containsOnlyDigits() {
+        String answer = answerGenerator.generateAnswer();
+        assertThat(answer).matches("\\d+");
+    }
+
+    @DisplayName("정답의 모든 숫자는 서로 다르다")
+    @Test
+    void generateAnswer_hasNoDuplicateDigits() {
+        String answer = answerGenerator.generateAnswer();
+        assertThat(answer.chars().distinct().count())
+                .isEqualTo(answer.length());
+    }
+}
diff --git a/src/test/java/BaseballAnswerJudgeTest.java b/src/test/java/BaseballAnswerJudgeTest.java
new file mode 100644
index 00000000..d5862401
--- /dev/null
+++ b/src/test/java/BaseballAnswerJudgeTest.java
@@ -0,0 +1,59 @@
+import model.AnswerJudge;
+import model.BaseballAnswerJudge;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class BaseballAnswerJudgeTest {
+
+    private AnswerJudge answerJudge;
+
+    @BeforeEach
+    void setup() {
+        answerJudge = new BaseballAnswerJudge();
+    }
+
+    @DisplayName("같은 위치의 숫자는 스트라이크로 판정한다")
+    @Test
+    void countStrikes_returnsCorrectCount_when_positionsMatch() {
+        int strikes = answerJudge.countStrikes("123", "153");
+        assertThat(strikes).isEqualTo(2);
+    }
+
+    @DisplayName("같은 위치의 숫자가 없으면 스트라이크는 0이다")
+    @Test
+    void countStrikes_returnsZero_when_noPositionMatches() {
+        int strikes = answerJudge.countStrikes("456", "123");
+        assertThat(strikes).isZero();
+    }
+
+    @DisplayName("모든 숫자와 위치가 같으면 스트라이크는 3이다")
+    @Test
+    void countStrikes_returnsThree_when_guessEqualsAnswer() {
+        int strikes = answerJudge.countStrikes("123", "123");
+        assertThat(strikes).isEqualTo(3);
+    }
+
+    @DisplayName("같은 위치의 숫자는 볼로 판정하지 않는다.")
+    @Test
+    void countBalls_returnsCorrectCount_when_positionsMatch() {
+        int balls = answerJudge.countBalls("123", "153");
+        assertThat(balls).isEqualTo(0);
+    }
+
+    @DisplayName("같은 숫자가 위치가 다르면 볼이다.")
+    @Test
+    void countBalls_returnsOne_when_noPositionMatches_OneValueMatches() {
+        int balls = answerJudge.countBalls("456", "124");
+        assertThat(balls).isEqualTo(1);
+    }
+
+    @DisplayName("같은 숫자가 없으면 볼은 0이다.")
+    @Test
+    void countBalls_returnsZero_when_noPositionMatches() {
+        int balls = answerJudge.countBalls("123", "456");
+        assertThat(balls).isZero();
+    }
+}
diff --git a/src/test/java/BaseballGameManagerTest.java b/src/test/java/BaseballGameManagerTest.java
new file mode 100644
index 00000000..34c08dc4
--- /dev/null
+++ b/src/test/java/BaseballGameManagerTest.java
@@ -0,0 +1,76 @@
+import model.AnswerGenerator;
+import model.AnswerJudge;
+import model.BaseballAnswerJudge;
+import model.BaseballGameManager;
+import model.GameManager;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class BaseballGameManagerTest {
+
+    private GameManager gameManager;
+    private AnswerJudge answerJudge;
+
+    @BeforeEach
+    void setup() {
+        AnswerGenerator fixedAnswerGenerator = () -> "123";
+        answerJudge = new BaseballAnswerJudge();
+        gameManager = new BaseballGameManager(fixedAnswerGenerator, answerJudge);
+    }
+
+    @DisplayName("게임 시작 전에는 플레이 상태가 아니다")
+    @Test
+    void isPlaying_returnsFalse_beforeGameStart() {
+        assertThat(gameManager.isPlaying()).isFalse();
+    }
+
+    @DisplayName("게임 시작 후에는 플레이 상태이다")
+    @Test
+    void isPlaying_returnsTrue_afterGameStart() {
+        gameManager.startGame();
+        assertThat(gameManager.isPlaying()).isTrue();
+    }
+
+    @DisplayName("추측 시 스트라이크와 볼 개수를 반환한다")
+    @Test
+    void guess_returnsStrikesAndBalls() {
+        gameManager.startGame();
+        int[] result = gameManager.guess("145");
+        assertThat(result[0]).isEqualTo(1);
+        assertThat(result[1]).isEqualTo(0);
+    }
+
+    @DisplayName("3스트라이크 시 게임이 종료된다")
+    @Test
+    void guess_endsGame_whenThreeStrikes() {
+        gameManager.startGame();
+        int[] result = gameManager.guess("123");
+        assertThat(result[0]).isEqualTo(3);
+        assertThat(gameManager.isPlaying()).isFalse();
+        assertThat(gameManager.isGameWon()).isTrue();
+    }
+
+    @DisplayName("3스트라이크가 아니면 게임이 계속된다")
+    @Test
+    void guess_continuesGame_whenNotThreeStrikes() {
+        gameManager.startGame();
+        gameManager.guess("456");
+        assertThat(gameManager.isPlaying()).isTrue();
+        assertThat(gameManager.isGameWon()).isFalse();
+    }
+
+    @DisplayName("게임 재시작 시 상태가 초기화된다")
+    @Test
+    void startGame_resetsState_afterGameWon() {
+        gameManager.startGame();
+        gameManager.guess("123");
+        assertThat(gameManager.isGameWon()).isTrue();
+
+        gameManager.startGame();
+        assertThat(gameManager.isPlaying()).isTrue();
+        assertThat(gameManager.isGameWon()).isFalse();
+    }
+}
diff --git a/src/test/java/BaseballInputValidatorTest.java b/src/test/java/BaseballInputValidatorTest.java
new file mode 100644
index 00000000..fb494d73
--- /dev/null
+++ b/src/test/java/BaseballInputValidatorTest.java
@@ -0,0 +1,57 @@
+import model.BaseballInputValidator;
+import model.InputValidator;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+import static org.assertj.core.api.Assertions.assertThatCode;
+
+public class BaseballInputValidatorTest {
+
+    private InputValidator validator;
+
+    @BeforeEach
+    void setup() {
+        validator = new BaseballInputValidator();
+    }
+
+    @DisplayName("올바른 입력은 예외가 발생하지 않는다")
+    @Test
+    void validate_doesNotThrow_whenValidInput() {
+        assertThatCode(() -> validator.validate("123"))
+                .doesNotThrowAnyException();
+    }
+
+    @DisplayName("3자리가 아니면 예외가 발생한다")
+    @Test
+    void validate_throwsException_whenLengthIsNotThree() {
+        assertThatThrownBy(() -> validator.validate("12"))
+                .isInstanceOf(IllegalArgumentException.class)
+                .hasMessageContaining("[ERROR]");
+    }
+
+    @DisplayName("숫자가 아닌 문자가 포함되면 예외가 발생한다")
+    @Test
+    void validate_throwsException_whenContainsNonDigit() {
+        assertThatThrownBy(() -> validator.validate("12a"))
+                .isInstanceOf(IllegalArgumentException.class)
+                .hasMessageContaining("[ERROR]");
+    }
+
+    @DisplayName("0이 포함되면 예외가 발생한다")
+    @Test
+    void validate_throwsException_whenContainsZero() {
+        assertThatThrownBy(() -> validator.validate("012"))
+                .isInstanceOf(IllegalArgumentException.class)
+                .hasMessageContaining("[ERROR]");
+    }
+
+    @DisplayName("중복된 숫자가 있으면 예외가 발생한다")
+    @Test
+    void validate_throwsException_whenHasDuplicates() {
+        assertThatThrownBy(() -> validator.validate("112"))
+                .isInstanceOf(IllegalArgumentException.class)
+                .hasMessageContaining("[ERROR]");
+    }
+}