diff --git a/wp-admin/includes/ms.php b/wp-admin/includes/ms.php
index b62e1d0b2d..9350a77dc8 100644
--- a/wp-admin/includes/ms.php
+++ b/wp-admin/includes/ms.php
@@ -135,6 +135,9 @@ function wpmu_delete_user( $id ) {
 	$id = (int) $id;
 	$user = new WP_User( $id );
 
+	if ( !$user->exists() )
+		return false;
+
 	do_action( 'wpmu_delete_user', $id );
 
 	$blogs = get_blogs_of_user( $id );
diff --git a/wp-admin/includes/user.php b/wp-admin/includes/user.php
index 1d60aa57e3..ea3bdbf6a9 100644
--- a/wp-admin/includes/user.php
+++ b/wp-admin/includes/user.php
@@ -240,6 +240,9 @@ function wp_delete_user( $id, $reassign = 'novalue' ) {
 	$id = (int) $id;
 	$user = new WP_User( $id );
 
+	if ( !$user->exists() )
+		return false;
+
 	// allow for transaction statement
 	do_action('delete_user', $id);