diff --git a/src/wp-includes/embed.php b/src/wp-includes/embed.php
index ac62f5ecfd..d961dc941b 100644
--- a/src/wp-includes/embed.php
+++ b/src/wp-includes/embed.php
@@ -226,7 +226,7 @@ function wp_maybe_load_embeds() {
  */
 function wp_embed_handler_youtube( $matches, $attr, $url, $rawattr ) {
 	global $wp_embed;
-	$embed = $wp_embed->autoembed( "https://youtube.com/watch?v={$matches[2]}" );
+	$embed = $wp_embed->autoembed( sprintf( "https://youtube.com/watch?v=%s", urlencode( $matches[2] ) ) );
 
 	/**
 	 * Filters the YoutTube embed output.