diff --git a/src/main/java/cnu/mvc/domain/member/MemberRepository.java b/src/main/java/cnu/mvc/domain/member/MemberRepository.java
index 1b273fc..5e1bdfe 100644
--- a/src/main/java/cnu/mvc/domain/member/MemberRepository.java
+++ b/src/main/java/cnu/mvc/domain/member/MemberRepository.java
@@ -5,6 +5,7 @@
 import java.util.HashMap;
 import java.util.Map;
 
+
 @Repository
 public class MemberRepository {
 
@@ -22,6 +23,11 @@ public Member findById(Long id) {
 
     // 구현
     public Member findByEmail(String email) {
+        for (Member member : store.values()){
+            if ( member.getEmail().equals(email)) {
+                return member;
+            }
+        }
         return null;
     }
 }
diff --git a/src/main/java/cnu/mvc/domain/member/MemberService.java b/src/main/java/cnu/mvc/domain/member/MemberService.java
index b8e785e..a5722a4 100644
--- a/src/main/java/cnu/mvc/domain/member/MemberService.java
+++ b/src/main/java/cnu/mvc/domain/member/MemberService.java
@@ -10,12 +10,22 @@ public class MemberService {
     private final MemberRepository memberRepository;
 
     public Member join(Member member){
+        // 이메일 중복 구현
+        if(findByEmail(member.getEmail()) != null ) {
+            throw new IllegalStateException("이미 존재하는 이메일 계정입니다.");
+        }
         return memberRepository.save(member);
     }
 
     public Member validateMember(String email, String pwd) {
-        Member findMember = findById(1L);
-        return findMember;
+        Member check_member = findByEmail(email);
+
+        if (check_member == null || !check_member.getPwd().equals(pwd)){
+            
+            throw new IllegalArgumentException("이메일 또는 비밀번호를 확인해주세요.");
+            
+        }
+        return check_member;
     }
 
     public Member findById(Long id) {
@@ -26,5 +36,4 @@ public Member findById(Long id) {
     public Member findByEmail(String email) {
         return memberRepository.findByEmail(email);
     }
-
 }