diff --git a/app/src/main/java/org/ntlab/irisclient/DrawingActivity.java b/app/src/main/java/org/ntlab/irisclient/DrawingActivity.java
index 52faef6..75df024 100644
--- a/app/src/main/java/org/ntlab/irisclient/DrawingActivity.java
+++ b/app/src/main/java/org/ntlab/irisclient/DrawingActivity.java
@@ -30,7 +30,7 @@
     private Integer drawingNum;
     private Integer drawingNow = 0;
     private Integer nowTime;
-    private Integer alphaNow; //今のペンの透明度
+    private Integer alphaNow=255; //今のペンの透明度
     private ToggleButton okToggleButton;
 
     @Override
@@ -197,9 +197,21 @@
                 drawingCanvas.clearCanvas();
             } else if (v.getId() == R.id.eraserButton) {//eraserButtonが押されたときの処理
                 drawingCanvas.setColor(Color.WHITE);
+                v.setBackgroundColor(Color.rgb(173,216,230));
+                findViewById(R.id.blackPenButton).setBackgroundColor(Color.rgb(211,211,211));
+                findViewById(R.id.blackPenButton).setScaleX(0.9f);
+                findViewById(R.id.blackPenButton).setScaleY(0.9f);
+                findViewById(R.id.eraserButton).setScaleX(1.0f);
+                findViewById(R.id.eraserButton).setScaleY(1.0f);
             } else if (v.getId() == R.id.blackPenButton) {
                 drawingCanvas.setColor(Color.BLACK);
                 drawingCanvas.setAlpha(alphaNow);
+                v.setBackgroundColor(Color.rgb(173,216,230));
+                findViewById(R.id.eraserButton).setBackgroundColor(Color.rgb(211,211,211));
+                findViewById(R.id.eraserButton).setScaleX(0.9f);
+                findViewById(R.id.eraserButton).setScaleY(0.9f);
+                findViewById(R.id.blackPenButton).setScaleX(1.0f);
+                findViewById(R.id.blackPenButton).setScaleY(1.0f);
             }
         }
     }