diff --git a/app/src/main/java/com/example/nemophila/LoginActivity.java b/app/src/main/java/com/example/nemophila/LoginActivity.java
index 5dd4b79..c3bdf20 100644
--- a/app/src/main/java/com/example/nemophila/LoginActivity.java
+++ b/app/src/main/java/com/example/nemophila/LoginActivity.java
@@ -31,11 +31,13 @@
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_login);
 
+        //Nemophilaと連携
         nemophila = (Nemophila) this.getApplication();
-//        if ((nemophila.getUid() != null) && (nemophila.getToken() != null)){
-//            Intent intent = new Intent(LoginActivity.this,MainActivity.class);
-//            startActivity(intent);
-//        }
+        //Nemophilaにtokenとuidがある場合ログイン画面をスキップ
+        if ((nemophila.getUid() != null) && (nemophila.getToken() != null)){
+            Intent intent = new Intent(LoginActivity.this,MainActivity.class);
+            startActivity(intent);
+        }
 
         //通信の初期化
         this.retrofit = new Retrofit.Builder()
@@ -44,10 +46,11 @@
                 .build();
         this.AccountsRest = retrofit.create(AccountsRest.class);
 
-
+//Loginボタンを押したとき
         findViewById(R.id.LoginButton).setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View view) {
+                //IDとpwの入力
                 EditText edituid = (EditText) findViewById(R.id.editTextUserID);
                 String uid = edituid.getText().toString();
                 EditText editpw = (EditText) findViewById(R.id.editTextTextNewPassword);
@@ -86,6 +89,7 @@
                 });
             }
         });
+//SignUpボタンを押したとき
         findViewById(R.id.SignUp).setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View view) {
@@ -93,6 +97,7 @@
                 startActivity(intent);
             }
         });
+//ForgotPasswordボタンを押したとき(処理未記入)
         findViewById(R.id.ForgotPW).setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View view) {
diff --git a/app/src/main/java/com/example/nemophila/SignUpActivity.java b/app/src/main/java/com/example/nemophila/SignUpActivity.java
index 0b1aa70..c3ab931 100644
--- a/app/src/main/java/com/example/nemophila/SignUpActivity.java
+++ b/app/src/main/java/com/example/nemophila/SignUpActivity.java
@@ -36,10 +36,11 @@
                 .build();
         this.AccountsRest = retrofit.create(AccountsRest.class);
 
-
+//アカウント新規製作
         findViewById(R.id.SignUpButton).setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View view) {
+                //Nameとpwを入力
                 EditText editname = (EditText) findViewById(R.id.editTextTextUserName);
                 String name = editname.getText().toString();
                 EditText editpw = (EditText) findViewById(R.id.editTextTextNewPassword);
@@ -73,5 +74,13 @@
                 });
             }
         });
+//Login画面に遷移
+        findViewById(R.id.LoginTrans).setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View view) {
+                Intent intent = new Intent(SignUpActivity.this,LoginActivity.class);
+                startActivity(intent);
+            }
+        });
     }
 }
\ No newline at end of file
diff --git a/app/src/main/res/layout/activity_sign_up.xml b/app/src/main/res/layout/activity_sign_up.xml
index ff65596..261ee26 100644
--- a/app/src/main/res/layout/activity_sign_up.xml
+++ b/app/src/main/res/layout/activity_sign_up.xml
@@ -47,4 +47,13 @@
         app:layout_constraintHorizontal_bias="0.498"
         app:layout_constraintStart_toStartOf="parent"
         app:layout_constraintTop_toBottomOf="@+id/editTextTextNewPassword" />
+
+    <Button
+        android:id="@+id/LoginTrans"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:text="I have an Account"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/SignUpButton" />
 </androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index d95b0d2..504a6fe 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -17,5 +17,6 @@
     <string name="signup">SignUp</string>
     <string name="userid">UserID</string>
     <string name="forgot_password">Forgot Password?</string>
+    <string name="button">Button</string>
 
 </resources>
\ No newline at end of file