diff --git a/types/argparse/index.d.ts b/types/argparse/index.d.ts
index cf4d1f648e..3330055b1f 100644
--- a/types/argparse/index.d.ts
+++ b/types/argparse/index.d.ts
@@ -69,6 +69,7 @@ export interface ArgumentParserOptions {
     prog?: string;
     usage?: string;
     version?: string;
+    debug?: boolean;
 }
 
 export interface ArgumentGroupOptions {