diff --git a/core-module/src/main/java/com/koa/coremodule/email/service/EmailSendService.java b/core-module/src/main/java/com/koa/coremodule/email/service/EmailSendService.java
index 379ada69..6943a5f6 100644
--- a/core-module/src/main/java/com/koa/coremodule/email/service/EmailSendService.java
+++ b/core-module/src/main/java/com/koa/coremodule/email/service/EmailSendService.java
@@ -15,9 +15,10 @@
 @Service
 @RequiredArgsConstructor
 public class EmailSendService {
-    private static final int LENGTH = 6;
-    private static final String MESSAGE= "인증번호는 %s 입니다.";
-    private static final String TITLE = "KOA 이메일 인증";
+    private static final int CODE_LENGTH = 6;
+    private static final String MESSAGE_TEMPLATE = "인증번호는 %s 입니다.";
+    private static final String EMAIL_TITLE = "KOA 이메일 인증";
+
     private final JavaMailSender emailSender;
     private final RedisUtils redisUtils;
 
@@ -26,27 +27,22 @@ public class EmailSendService {
 
     public void sendEmail(String email) {
         String code = createCode();
-        SimpleMailMessage emailForm = createEmailForm(email, TITLE, String.format(MESSAGE, code));
+        String messageText = String.format(MESSAGE_TEMPLATE, code);
+        SimpleMailMessage emailForm = createEmailForm(email, EMAIL_TITLE, messageText);
         emailSender.send(emailForm);
         redisUtils.setDataExpire(email, code, authCodeExpirationMillis);
     }
 
     private String createCode() {
-        try {
-            Random random = SecureRandom.getInstanceStrong();
-            StringBuilder builder = new StringBuilder();
-            for (int i = 0; i < LENGTH; i++) {
-                builder.append(random.nextInt(10));
-            }
-            return builder.toString();
-        } catch (NoSuchAlgorithmException e) {
-            throw new CreateCodeException(Error.CREATE_CODE_FAIL);
+        Random random = new Random();
+        StringBuilder codeBuilder = new StringBuilder(CODE_LENGTH);
+        for (int i = 0; i < CODE_LENGTH; i++) {
+            codeBuilder.append(random.nextInt(10));
         }
+        return codeBuilder.toString();
     }
 
-    private SimpleMailMessage createEmailForm(String toEmail,
-                                              String title,
-                                              String text) {
+    private SimpleMailMessage createEmailForm(String toEmail, String title, String text) {
         SimpleMailMessage message = new SimpleMailMessage();
         message.setTo(toEmail);
         message.setSubject(title);
diff --git a/core-module/src/main/java/com/koa/coremodule/member/application/service/EmailVerificationUseCase.java b/core-module/src/main/java/com/koa/coremodule/member/application/service/EmailVerificationUseCase.java
index b97a8f7a..deab08a4 100644
--- a/core-module/src/main/java/com/koa/coremodule/member/application/service/EmailVerificationUseCase.java
+++ b/core-module/src/main/java/com/koa/coremodule/member/application/service/EmailVerificationUseCase.java
@@ -16,7 +16,6 @@ public class EmailVerificationUseCase {
     private final MemberQueryService memberQueryService;
 
     public void sendVerificationEmail(String email) {
-        memberQueryService.checkEmailExist(email);
         emailSendService.sendEmail(email);
     }