diff --git a/FirebaseAuth/CHANGELOG.md b/FirebaseAuth/CHANGELOG.md
index fe6bce0fb37..795b602922e 100644
--- a/FirebaseAuth/CHANGELOG.md
+++ b/FirebaseAuth/CHANGELOG.md
@@ -1,6 +1,7 @@
 # Unreleased
 - [fixed] Fix a `fatalError` unenrolling from MFA. An invalid user token now throws an
   `invalidUserToken` error instead of crashing. (#14663)
+- [fixed] Fix the parameter from "languageCode" to "lang" in ActionCodeURL (#14664)
 
 # 11.9.0
 - [changed] Using reCAPTCHA Enterprise and Firebase Auth requires reCAPTCHA
diff --git a/FirebaseAuth/Sources/Swift/ActionCode/ActionCodeURL.swift b/FirebaseAuth/Sources/Swift/ActionCode/ActionCodeURL.swift
index 29bb8070c1a..16c28437f4f 100644
--- a/FirebaseAuth/Sources/Swift/ActionCode/ActionCodeURL.swift
+++ b/FirebaseAuth/Sources/Swift/ActionCode/ActionCodeURL.swift
@@ -56,7 +56,7 @@ import Foundation
     } else {
       continueURL = nil
     }
-    languageCode = queryItems["languageCode"]
+    languageCode = queryItems["lang"]
   }
 
   class func parseURL(_ urlString: String) -> [String: String] {