diff --git a/app/src/main/java/com/example/oplogy/SetUpActivity.java b/app/src/main/java/com/example/oplogy/SetUpActivity.java
index 9daa365..31aac2f 100644
--- a/app/src/main/java/com/example/oplogy/SetUpActivity.java
+++ b/app/src/main/java/com/example/oplogy/SetUpActivity.java
@@ -15,6 +15,7 @@ public class SetUpActivity extends FragmentActivity
 
     private TextView startTime;
     private TextView endTime;
+    private boolean isStartTimeSelected = true; // デフォルトはstartTimeを選択
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -23,21 +24,37 @@ public class SetUpActivity extends FragmentActivity
 
         startTime = findViewById(R.id.startTime);
         endTime = findViewById(R.id.endTime);
+
+        startTime.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View v) {
+                isStartTimeSelected = true;
+                showTimePickerDialog();
+            }
+        });
+
+        endTime.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View v) {
+                isStartTimeSelected = false;
+                showTimePickerDialog();
+            }
+        });
     }
 
     @Override
     public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
+        String str = String.format(Locale.US, "%d:%d", hourOfDay, minute); // Textviewに保存する形式を設定
 
-        String str = String.format(Locale.US, "%d:%d", hourOfDay, minute);
-
-        startTime.setText(str);
-        endTime.setText(str);
-
+        if (isStartTimeSelected) { //押した場所を判定して、押したほうにだけ挿入する
+            startTime.setText(str);
+        } else {
+            endTime.setText(str);
+        }
     }
 
-    public void showTimePickerDialog(View v) {
+    private void showTimePickerDialog() { // Dialogを表示する
         DialogFragment newFragment = new TimePick();
         newFragment.show(getSupportFragmentManager(), "timePicker");
-
     }
-}
+}
\ No newline at end of file
diff --git a/app/src/main/java/com/example/oplogy/TimePick.java b/app/src/main/java/com/example/oplogy/TimePick.java
index c2caaa1..3493c6d 100644
--- a/app/src/main/java/com/example/oplogy/TimePick.java
+++ b/app/src/main/java/com/example/oplogy/TimePick.java
@@ -14,7 +14,7 @@ public class TimePick extends DialogFragment implements
 
     @NonNull
     @Override
-    public Dialog onCreateDialog(Bundle savedInstanceState) {
+    public Dialog onCreateDialog(Bundle savedInstanceState) { // TimePeckerの生成
         final Calendar c = Calendar.getInstance();
         int hour = c.get(Calendar.HOUR_OF_DAY);
         int minute = c.get(Calendar.MINUTE);
diff --git a/app/src/main/res/layout/activity_set_up.xml b/app/src/main/res/layout/activity_set_up.xml
index fdc7fb8..bdfb28d 100644
--- a/app/src/main/res/layout/activity_set_up.xml
+++ b/app/src/main/res/layout/activity_set_up.xml
@@ -8,6 +8,16 @@
     android:orientation="vertical"
     android:gravity="center">
 
+
+    <TextView
+        android:id="@+id/toMain"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:gravity="left"
+        android:text="🔙"
+        android:textSize="50dp"
+        tools:ignore="RtlCompat" />
+
     <TextView
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
@@ -79,7 +89,6 @@
             android:id="@+id/startTime"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
-            android:onClick="showTimePickerDialog"
             android:autofillHints=""
             android:inputType=""
             tools:ignore="LabelFor"/>
@@ -103,7 +112,6 @@
             android:id="@+id/endTime"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
-            android:onClick="showTimePickerDialog"
             android:autofillHints=""
             android:inputType=""
             tools:ignore="LabelFor"/>