diff --git a/src/main/java/org/ntlab/acanthus_server/resources/gallery/StrokesRest.java b/src/main/java/org/ntlab/acanthus_server/resources/gallery/StrokesRest.java
index 9428e5e..5f22986 100644
--- a/src/main/java/org/ntlab/acanthus_server/resources/gallery/StrokesRest.java
+++ b/src/main/java/org/ntlab/acanthus_server/resources/gallery/StrokesRest.java
@@ -53,7 +53,7 @@
         Stroke stroke = new Stroke();
         stroke.addStrokes(pen, color, thick); // 線の情報を追加
         strokes.add(stroke);
-        stroke.setStrokeNo(strokes.size());   // strokeNoに現在のstrokesのsizeを入れる
+        stroke.setStrokeNo(strokes.size()-1);   // strokeNoに現在のstrokesのsizeを入れる
 //        if(animation != null) {
 //            this.Test.setStrokes(pen, color, thick);
 //        }else{