diff --git a/lib/ansible/modules/network/aci/aci_aaa_user_certificate.py b/lib/ansible/modules/network/aci/aci_aaa_user_certificate.py
index 275c4ac9a72..eef282c2081 100644
--- a/lib/ansible/modules/network/aci/aci_aaa_user_certificate.py
+++ b/lib/ansible/modules/network/aci/aci_aaa_user_certificate.py
@@ -29,6 +29,7 @@ options:
   aaa_user:
     description:
     - The name of the user to add a certificate to.
+    required: yes
   aaa_user_type:
     description:
     - Whether this is a normal user or an appuser.