diff --git a/templates/user/auth/signup_inner.tmpl b/templates/user/auth/signup_inner.tmpl
index 28138b8f3..03f46de1f 100644
--- a/templates/user/auth/signup_inner.tmpl
+++ b/templates/user/auth/signup_inner.tmpl
@@ -122,13 +122,12 @@
 				}				
 			}
 			return obj;
-		};
-		
+		};		
 		var sharedUser = getUrlParams()['sharedUser'];
 		if (sharedUser) {
 			setTimeout(function() {
 				$('.invitation_tips').show().find('.__invitation_code__').text(sharedUser);
-				$('input#invitation_code').val(sharedUser).attr('disabled', true);
+				$('input#invitation_code').val(sharedUser).attr('readonly', true);
 			}, 20);
 		}
 	})();