diff --git a/src/main/java/nlib/cmm/fileupload/FileUploadController.java b/src/main/java/nlib/cmm/fileupload/FileUploadController.java
index 139b5e12..f90e20a1 100644
--- a/src/main/java/nlib/cmm/fileupload/FileUploadController.java
+++ b/src/main/java/nlib/cmm/fileupload/FileUploadController.java
@@ -156,7 +156,7 @@ public class FileUploadController extends NlibCommonController {
 				
 				// 허용 파일 확장자 
 				String acceptableExtList = StringUtil.getString(NlibProperty.getString("fileupload.acceptable.ext"), null);
-				if(acceptableExtList != null) acceptableExtList = "," + acceptableExtList.trim();
+				if(acceptableExtList != null) acceptableExtList = "," + acceptableExtList.trim().toLowerCase();
 				boolean acceptableExt = false;
 				
 				// 최대 파일크기
@@ -189,7 +189,7 @@ public class FileUploadController extends NlibCommonController {
 
 					// 파일 확장자 
 					int index = orignlFileNm.lastIndexOf(".");
-					String fileExt = (index < 1 ? "" : orignlFileNm.substring(index + 1));
+					String fileExt = (index < 1 ? "" : orignlFileNm.substring(index + 1)).toLowerCase();
 					
 					if(acceptableExtList != null) {