diff --git a/extensions/git/src/git.ts b/extensions/git/src/git.ts
index dcb3b4eb65f..327903aa959 100644
--- a/extensions/git/src/git.ts
+++ b/extensions/git/src/git.ts
@@ -1168,7 +1168,7 @@ export class Repository {
 	}
 
 	async config(command: string, scope: string, key: string, value: any = null, options: SpawnOptions = {}): Promise<string> {
-		const args = ['config', command];
+		const args = ['config', `--${command}`];
 
 		if (scope) {
 			args.push(`--${scope}`);
diff --git a/extensions/git/src/repository.ts b/extensions/git/src/repository.ts
index e1b71d87f0a..28f9b70b3b3 100644
--- a/extensions/git/src/repository.ts
+++ b/extensions/git/src/repository.ts
@@ -1088,7 +1088,7 @@ export class Repository implements Disposable {
 	}
 
 	setConfig(key: string, value: string): Promise<string> {
-		return this.run(Operation.Config(false), () => this.repository.config('set', 'local', key, value));
+		return this.run(Operation.Config(false), () => this.repository.config('add', 'local', key, value));
 	}
 
 	log(options?: LogOptions & { silent?: boolean }): Promise<Commit[]> {