diff --git a/app/src/main/java/com/example/citrusclient/views/LoginActivity.java b/app/src/main/java/com/example/citrusclient/views/LoginActivity.java
index bae33bb..d38374d 100644
--- a/app/src/main/java/com/example/citrusclient/views/LoginActivity.java
+++ b/app/src/main/java/com/example/citrusclient/views/LoginActivity.java
@@ -2,18 +2,32 @@
 
 import android.content.Intent;
 import android.os.Bundle; //
+import android.os.Handler;
 import android.view.View;
 import android.widget.Button;
 
+import android.widget.EditText;
+import android.widget.TextView;
 import androidx.activity.EdgeToEdge;
 import androidx.appcompat.app.AppCompatActivity; //
 import androidx.core.graphics.Insets;
 import androidx.core.view.ViewCompat;
 import androidx.core.view.WindowInsetsCompat;
+import com.example.citrusclient.Citrus;
 import com.example.citrusclient.R;
+import com.example.citrusclient.rest.AccountsRest;
+import retrofit2.Call;
+import retrofit2.Callback;
+import retrofit2.Response;
+import retrofit2.Retrofit;
+import retrofit2.converter.jackson.JacksonConverterFactory;
 
 public class LoginActivity extends AppCompatActivity {
+    private Retrofit retrofit;
+    private AccountsRest accountsRest;
+    private Citrus citrus;
 
+    //画面起動時
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -25,23 +39,87 @@
             return insets;
         });
 
-        // username = findViewById(R.id.username);
-        // password = findViewById(R.id.password);
-        // loginButton = findViewById(R.id.loginButton);
+        //citrusと連携
+        citrus = (Citrus) this.getApplication();
+
+        //通信の初期化
+        this.retrofit = new Retrofit.Builder()
+            .baseUrl("http://nitta-lab-www.is.konan-u.ac.jp/citrus/")
+            .addConverterFactory(JacksonConverterFactory.create())
+            .build();
+        this.accountsRest = retrofit.create(AccountsRest.class);
 
         Button loginButton = (Button)findViewById(R.id.loginButton);
         loginButton.setOnClickListener(new View.OnClickListener(){
 
             public void onClick(View v){
-                Intent intent = new Intent(LoginActivity.this,MainActivity.class);
-                startActivity(intent);
+                //テキストを文字列で認識
+                EditText editid = (EditText) findViewById(R.id.username);
+                String id = editid.getText().toString().trim();
+                EditText editpw = (EditText) findViewById(R.id.password);
+                String pw = editpw.getText().toString().trim();
+                final Handler handler = new Handler();
+
+                //入力欄が空欄の時
+                if(id.isEmpty() && pw.isEmpty() && id.trim().isEmpty() && pw.trim().isEmpty()){
+                    System.out.println("不適切入力");
+                    ((TextView)findViewById(R.id.textView_respons)).setText("適切に入力してください");
+
+                //Intent intent = new Intent(LoginActivity.this,MainActivity.class);
+                //startActivity(intent);
+
+                }else if(!id.isEmpty() && !pw.isEmpty() && !id.trim().isEmpty() && !pw.trim().isEmpty() ){
+                    //入力欄が全て適切に入力された場合の処理
+                    Call<String> call = accountsRest.login(id,pw);
+                    call.enqueue(new Callback<String>() {
+                        @Override
+                        public void onResponse(Call<String> call, Response<String> response) {
+                            if (response.isSuccessful()){
+                                if (!response.body().equals("null")) {
+                                    System.out.println("通信成功");
+                                    //端末にtoken.id登録
+                                    String token = response.body();
+                                    citrus.setToken(token);
+                                    citrus.setAccountId(id);
+
+                                    //画面遷移
+                                    handler.post(new Runnable() {
+                                        @Override
+                                        public void run() {
+                                            Intent intent = new Intent(LoginActivity.this,
+                                                MainActivity.class);
+                                            startActivity(intent);
+                                        }
+                                    });
+                                }else{
+                                    ((TextView)findViewById(R.id.textView_respons)).setText(("パスワードが間違っています"));
+
+                                }
+
+                            }else{
+                                //通信可能（ただしエラーが発生した場合）
+                                //404がPW入力されてないときだけど、前で定義しているからいらないよね..?
+                                System.out.println("通信可能");
+                                if(response.code()==404){
+                                    ((TextView)findViewById(R.id.textView_respons)).setText(("IDが間違っています"));
+                                }
+                            }
+                        }
+                        //通信失敗
+                        @Override
+                        public void onFailure(Call<String> call, Throwable t) {
+                            System.out.println("通信失敗");
+                            System.out.println(t);
+                        }
+                    });
+                }
             }
         });
         Button newButton = (Button)findViewById(R.id.newAccount);
         newButton.setOnClickListener(new View.OnClickListener(){
 
             public void onClick(View v){
-                Intent intent = new Intent(LoginActivity.this,MainActivity.class);
+                Intent intent = new Intent(LoginActivity.this,SignUpActivity.class);
                 startActivity(intent);
             }
         });