diff --git a/designer-base/src/main/java/com/fr/design/mainframe/JTemplateNameHelper.java b/designer-base/src/main/java/com/fr/design/mainframe/JTemplateNameHelper.java
index 4e201a5ef..22d5985ba 100644
--- a/designer-base/src/main/java/com/fr/design/mainframe/JTemplateNameHelper.java
+++ b/designer-base/src/main/java/com/fr/design/mainframe/JTemplateNameHelper.java
@@ -53,6 +53,9 @@ public class JTemplateNameHelper {
      * @Date 2021/4/9 11:13
      **/
     private static Integer getFileNameIndex(String prefix, String fileName) {
+		if (fileName.length() <= prefix.length()) {
+            return null;
+        }
         char[] chars = new char[fileName.length()];
         int i = 0;
         for (; i < fileName.length(); i++) {