diff --git a/app/src/main/java/com/example/cosmosclient/views/SigninActivity.java b/app/src/main/java/com/example/cosmosclient/views/SigninActivity.java
index de06c2c..b3e02fe 100644
--- a/app/src/main/java/com/example/cosmosclient/views/SigninActivity.java
+++ b/app/src/main/java/com/example/cosmosclient/views/SigninActivity.java
@@ -3,6 +3,8 @@
 import android.content.Intent;
 import android.support.v7.app.AppCompatActivity;
 import android.os.Bundle;
+import android.text.Editable;
+import android.text.TextWatcher;
 import android.view.View;
 import android.widget.Button;
 import android.widget.EditText;
@@ -17,6 +19,9 @@
 import retrofit2.converter.jackson.JacksonConverterFactory;
 
 public class SigninActivity extends AppCompatActivity {
+    private boolean uIdEnable;
+    private boolean pwEnable;
+    Button SigninButton;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -24,12 +29,19 @@
         setContentView(R.layout.activity_signin);
 
         //各種IDを取得
-        Button SigninButton = findViewById(R.id.SigninButton);
+        SigninButton = findViewById(R.id.SigninButton);
         Button SignupButton = findViewById(R.id.SignupButton);
         final EditText NameText = findViewById(R.id.NameText);
         final EditText PasswordText = findViewById(R.id.PasswordText);
         Button ForgotPasswordButton = findViewById(R.id.ForgotPasswordButton);
 
+        //ボタン無効化
+        SigninButton.setEnabled(false);
+
+        //TextWatcherで入力監視
+        NameText.addTextChangedListener(new SigninActivity.GenericTextWatcher(NameText));
+        PasswordText.addTextChangedListener(new SigninActivity.GenericTextWatcher(PasswordText));
+
         //retrofitの処理
         final Retrofit retrofit = new Retrofit.Builder()
                 .baseUrl("http://nitta-lab-www.is.konan-u.ac.jp/cosmos/")
@@ -61,6 +73,7 @@
                             finish();
 
                         }else{
+                            //onFailureでキャッチできないエラーの処理
                             Toast.makeText(SigninActivity.this,
                                     "通信エラー",Toast.LENGTH_SHORT).show();
                         }
@@ -98,4 +111,42 @@
             }
         });
     }
+    private class GenericTextWatcher implements TextWatcher{
+        private View view;
+
+        private GenericTextWatcher(View view){
+            this.view = view;
+        }
+
+        @Override
+        public  void beforeTextChanged(CharSequence s, int start, int count,int after){/*記述不要*/};
+        @Override
+        public void onTextChanged(CharSequence s, int start, int before, int count){/*記述不要*/};
+
+        @Override
+        public void afterTextChanged(Editable s){
+            switch(view.getId()) {
+                case R.id.NameText:
+                    if (s.length() > 0) {
+                        uIdEnable = true;
+                    } else {
+                        uIdEnable = false;
+                    }
+                    break;
+                case R.id.PasswordText:
+                    if(s.length()>5){
+                        pwEnable=true;
+                    }else{
+                        pwEnable=false;
+                    }
+                    break;
+            }
+            //ボタン有効＆無効
+            if(uIdEnable && pwEnable ){
+                SigninButton.setEnabled(true);
+            }else{
+                SigninButton.setEnabled(false);
+            }
+        }
+    }
 }