diff --git a/lib/acid/httpclient.lua b/lib/acid/httpclient.lua
index c280fd8..f372da8 100644
--- a/lib/acid/httpclient.lua
+++ b/lib/acid/httpclient.lua
@@ -322,8 +322,21 @@ function _M.send_request( self, uri, opts )
 
     local body = opts.body or ''
     local headers = opts.headers or {}
-    headers.Host = headers.Host or self.ip
-    if #body > 0 and headers['Content-Length'] == nil then
+    local host = headers['Host']
+    local content_length = headers['Content-Length']
+    local range = headers['Range']
+
+    if opts.header_case_sensitive then
+        host = headers['host'] or host
+        content_length = headers['content-length'] or content_length
+        range = headers['range'] or range
+    end
+
+    if host == nil then
+        headers['Host'] = self.ip
+    end
+
+    if content_length == nil and #body > 0 then
         headers['Content-Length'] = #body
     end
 
@@ -342,8 +355,8 @@ function _M.send_request( self, uri, opts )
             uri = self.uri,
         })
 
-        if headers['Range'] ~= nil then
-            local r, err, _ = _M.parse_request_range(headers['Range'], nil)
+        if range ~= nil then
+            local r, err, _ = _M.parse_request_range(range, nil)
             if err == nil then
                 self.log.range = {from = r.start, to = r['end']}
             end
diff --git a/t/httpclient_test.t b/t/httpclient_test.t
index 70bf498..44e3176 100644
--- a/t/httpclient_test.t
+++ b/t/httpclient_test.t
@@ -473,3 +473,41 @@ keep-alive
 1
 --- no_error_log
 [error]
+
+
+=== TEST 12: test request option header case sensitive
+--- http_config eval: $::HttpConfig
+--- config
+    location /t {
+        content_by_lua '
+            local httpclient = require("acid.httpclient")
+
+            local cli = httpclient:new( "127.0.0.1", ngx.var.server_port)
+            local err, errmes = cli:request( "/b", {headers = {host = "partition.bscstorage.com"},
+                                                    header_case_sensitive = true})
+            if err ~= nil then
+                ngx.log(ngx.ERR, "requset error")
+                return
+            end
+
+            ngx.say(cli.status)
+            return
+        ';
+    }
+
+    location /b {
+        content_by_lua '
+            local hdr = ngx.req.get_headers(0)
+            if hdr["host"] ~= "partition.bscstorage.com" then
+                ngx.status = 400
+            else
+                ngx.status = 200
+            end
+        ';
+    }
+--- request
+GET /t
+--- response_body
+200
+--- no_error_log
+[error]