diff --git a/packages/filesystem/src/browser/file-service.ts b/packages/filesystem/src/browser/file-service.ts
index 89493b5e5774e..0e51c04a0beb2 100644
--- a/packages/filesystem/src/browser/file-service.ts
+++ b/packages/filesystem/src/browser/file-service.ts
@@ -66,7 +66,6 @@ import { EncodingService, ResourceEncoding, DecodeStreamResult } from '@theia/co
 import { Mutable } from '@theia/core/lib/common/types';
 import { readFileIntoStream } from '../common/io';
 import { FileSystemWatcherErrorHandler } from './filesystem-watcher-error-handler';
-import { FileSystemUtils } from '../common/filesystem-utils';
 
 export interface FileOperationParticipant {
 
@@ -1117,13 +1116,6 @@ export class FileService {
         // validation
         const { exists, isSameResourceWithDifferentPathCase } = await this.doValidateMoveCopy(sourceProvider, source, targetProvider, target, mode, overwrite);
 
-        // if target exists get valid target
-        if (exists && !overwrite) {
-            const parent = await this.resolve(target.parent);
-            const name = target.path.name + '_copy';
-            target = FileSystemUtils.generateUniqueResourceURI(target.parent, parent, name, target.path.ext);
-        }
-
         // delete as needed (unless target is same resource with different path case)
         if (exists && !isSameResourceWithDifferentPathCase && overwrite) {
             await this.delete(target, { recursive: true });
diff --git a/packages/filesystem/src/browser/file-tree/file-tree-model.ts b/packages/filesystem/src/browser/file-tree/file-tree-model.ts
index 1f8440e41157d..5b631eb037bdd 100644
--- a/packages/filesystem/src/browser/file-tree/file-tree-model.ts
+++ b/packages/filesystem/src/browser/file-tree/file-tree-model.ts
@@ -24,6 +24,7 @@ import { FileService } from '../file-service';
 import { FileOperationError, FileOperationResult, FileChangesEvent, FileChangeType, FileChange, FileOperation, FileOperationEvent } from '../../common/files';
 import { MessageService } from '@theia/core/lib/common/message-service';
 import { EnvVariablesServer } from '@theia/core/lib/common/env-variables';
+import { FileSystemUtils } from '../../common';
 
 @injectable()
 export class FileTreeModel extends TreeModelImpl implements LocationService {
@@ -148,8 +149,13 @@ export class FileTreeModel extends TreeModelImpl implements LocationService {
     }
 
     async copy(source: URI, target: Readonly<FileStatNode>): Promise<URI> {
-        const targetUri = target.uri.resolve(source.path.base);
+        let targetUri = target.uri.resolve(source.path.base);
         try {
+            if (source.path.toString() === target.uri.path.toString()) {
+                const parent = await this.fileService.resolve(source.parent);
+                const name = source.path.name + '_copy';
+                targetUri = FileSystemUtils.generateUniqueResourceURI(source.parent, parent, name, source.path.ext);
+            }
             await this.fileService.copy(source, targetUri);
         } catch (e) {
             this.messageService.error(e.message);