diff --git a/wp-includes/class-oembed.php b/wp-includes/class-oembed.php
index a3eab801a1..46d5f6290d 100644
--- a/wp-includes/class-oembed.php
+++ b/wp-includes/class-oembed.php
@@ -220,6 +220,9 @@ class WP_oEmbed {
 			return false;
 		}
 
+		if ( ! class_exists( 'DOMDocument' ) )
+			return false;
+
 		$errors = libxml_use_internal_errors( true );
 		$old_value = null;
 		if ( function_exists( 'libxml_disable_entity_loader' ) ) {