diff --git a/spine-unity/Assets/Spine/Editor/spine-unity/Editor/Utility/AssetUtility.cs b/spine-unity/Assets/Spine/Editor/spine-unity/Editor/Utility/AssetUtility.cs
index 2ea058944..2261ec2b9 100644
--- a/spine-unity/Assets/Spine/Editor/spine-unity/Editor/Utility/AssetUtility.cs
+++ b/spine-unity/Assets/Spine/Editor/spine-unity/Editor/Utility/AssetUtility.cs
@@ -497,7 +497,7 @@ namespace Spine.Unity.Editor {
 
 		static void AddDependentAtlasIfImageChanged (List<string> atlasPaths, List<string> imagePaths) {
 			foreach (string imagePath in imagePaths) {
-				string atlasPath = imagePath.Replace(".png", ".atlas.txt");
+				string atlasPath = Path.ChangeExtension(imagePath, ".atlas.txt");
 				if (!System.IO.File.Exists(atlasPath))
 					continue;