diff --git src/wp-includes/admin-bar.php src/wp-includes/admin-bar.php
index de33f54..aa9f568 100644
--- src/wp-includes/admin-bar.php
+++ src/wp-includes/admin-bar.php
@@ -150,6 +150,13 @@ function wp_admin_bar_wp_menu( $wp_admin_bar ) {
 		'title'     => __('Feedback'),
 		'href'      => __('https://wordpress.org/support/forum/requests-and-feedback'),
 	) );
+
+	// Add network site search
+	$wp_admin_bar->add_menu( array(
+		'parent' => 'my-sites-list',
+		'id'     => 'my-sites-search',
+		'title'  => '<input type="search" placeholder="'. __( 'Search sites' ) .'" />',
+	) );
 }
 
 /**
diff --git src/wp-includes/css/admin-bar.css src/wp-includes/css/admin-bar.css
index 86ad745..ef199cf 100644
--- src/wp-includes/css/admin-bar.css
+++ src/wp-includes/css/admin-bar.css
@@ -540,7 +540,18 @@ html:lang(he-il) .rtl #wpadminbar *  {
 	content: "\f102";
 }
 
+#wpadminbar #wp-admin-bar-my-sites #wp-admin-bar-my-sites-search {
+	height: 38px;
+}
+#wpadminbar #wp-admin-bar-my-sites #wp-admin-bar-my-sites-search .ab-item {
+	height: 34px;
+}
 
+#wpadminbar #wp-admin-bar-my-sites #wp-admin-bar-my-sites-search input[type="search"] {
+	padding: 0 2px;
+	width: 95%;
+	width: calc( 100% - 6px );
+}
 
 /**
  * Comments
diff --git src/wp-includes/js/admin-bar.js src/wp-includes/js/admin-bar.js
index 10d2954..b0f2647 100644
--- src/wp-includes/js/admin-bar.js
+++ src/wp-includes/js/admin-bar.js
@@ -93,6 +93,13 @@ if ( typeof(jQuery) != 'undefined' ) {
 			}).focus().select();
 		});
 
+		$('#wp-admin-bar-my-sites-search input').bind('keyup search', function() {
+			var searchValRegex = new RegExp( $(this).val(), 'i');
+			$('#wp-admin-bar-my-sites-list > li.menupop').hide().filter(function() {
+				return searchValRegex.test( $(this).children('a').text() );
+			}).show();
+		});
+
 		$('#wpadminbar li.menupop > .ab-item').bind('keydown.adminbar', function(e){
 			if ( e.which != 13 )
 				return;