diff --git a/src/validator/validator.ts b/src/validator/validator.ts
index c0795fe5..076fccb4 100644
--- a/src/validator/validator.ts
+++ b/src/validator/validator.ts
@@ -24,7 +24,7 @@ export type ValidationFunction<
 type ExcludeResponseType<T> = T extends Response & TypedResponse<any> ? never : T
 
 const jsonRegex = /^application\/([a-z-\.]+\+)?json$/
-const multipartRegex = /^multipart\/form-data(; boundary=[A-Za-z0-9'()+_,\-./:=?]+)?$/
+const multipartRegex = /^multipart\/form-data(; boundary=[A-Za-z0-9'"()+_,\-./:=?]+)?$/
 const urlencodedRegex = /^application\/x-www-form-urlencoded$/
 
 export const validator = <