diff --git a/src/wp-admin/includes/admin-filters.php b/src/wp-admin/includes/admin-filters.php
index e80c111dde..33354cb073 100644
--- a/src/wp-admin/includes/admin-filters.php
+++ b/src/wp-admin/includes/admin-filters.php
@@ -80,6 +80,7 @@ add_filter( 'heartbeat_received', 'wp_refresh_post_lock', 10, 3 );
 add_filter( 'heartbeat_received', 'heartbeat_autosave', 500, 2 );
 
 add_filter( 'wp_refresh_nonces', 'wp_refresh_post_nonces', 10, 3 );
+add_filter( 'wp_refresh_nonces', 'wp_refresh_metabox_loader_nonces', 10, 2 );
 add_filter( 'wp_refresh_nonces', 'wp_refresh_heartbeat_nonces' );
 
 add_filter( 'heartbeat_settings', 'wp_heartbeat_set_suspension' );
diff --git a/src/wp-admin/includes/misc.php b/src/wp-admin/includes/misc.php
index 94337fee7d..65cf69ab31 100644
--- a/src/wp-admin/includes/misc.php
+++ b/src/wp-admin/includes/misc.php
@@ -1255,6 +1255,41 @@ function wp_refresh_post_nonces( $response, $data, $screen_id ) {
 	return $response;
 }
 
+/**
+ * Refresh nonces used with meta boxes in the block editor.
+ *
+ * @since 6.1.0
+ *
+ * @param array  $response  The Heartbeat response.
+ * @param array  $data      The $_POST data sent.
+ * @return array The Heartbeat response.
+ */
+function wp_refresh_metabox_loader_nonces( $response, $data ) {
+	if ( empty( $data['wp-refresh-metabox-loader-nonces'] ) ) {
+		return $response;
+	}
+
+	$received = $data['wp-refresh-metabox-loader-nonces'];
+	$post_id  = (int) $received['post_id'];
+
+	if ( ! $post_id ) {
+		return $response;
+	}
+
+	if ( ! current_user_can( 'edit_post', $post_id ) ) {
+		return $response;
+	}
+
+	$response['wp-refresh-metabox-loader-nonces'] = array(
+		'replace' => array(
+			'metabox_loader_nonce' => wp_create_nonce( 'meta-box-loader' ),
+			'_wpnonce'             => wp_create_nonce( 'update-post_' . $post_id ),
+		),
+	);
+
+	return $response;
+}
+
 /**
  * Adds the latest Heartbeat and REST-API nonce to the Heartbeat response.
  *
diff --git a/src/wp-admin/includes/post.php b/src/wp-admin/includes/post.php
index 8eb0368220..1abe542316 100644
--- a/src/wp-admin/includes/post.php
+++ b/src/wp-admin/includes/post.php
@@ -2334,6 +2334,50 @@ function the_block_editor_meta_boxes() {
 		wp_add_inline_script( 'wp-lists', $script );
 	}
 
+	/*
+	 * Refresh nonces used by the meta box loader.
+	 *
+	 * The logic is very similar to that provided by post.js for the classic editor.
+	 */
+	$script = "( function( $ ) {
+		var check, timeout;
+
+		function schedule() {
+			check = false;
+			window.clearTimeout( timeout );
+			timeout = window.setTimeout( function() { check = true; }, 300000 );
+		}
+
+		$( document ).on( 'heartbeat-send.wp-refresh-nonces', function( e, data ) {
+			var post_id, \$authCheck = $( '#wp-auth-check-wrap' );
+
+			if ( check || ( \$authCheck.length && ! \$authCheck.hasClass( 'hidden' ) ) ) {
+				if ( ( post_id = $( '#post_ID' ).val() ) && $( '#_wpnonce' ).val() ) {
+					data['wp-refresh-metabox-loader-nonces'] = {
+						post_id: post_id
+					};
+				}
+			}
+		}).on( 'heartbeat-tick.wp-refresh-nonces', function( e, data ) {
+			var nonces = data['wp-refresh-metabox-loader-nonces'];
+
+			if ( nonces ) {
+				if ( nonces.replace ) {
+					if ( nonces.replace.metabox_loader_nonce && window._wpMetaBoxUrl && wp.url ) {
+						window._wpMetaBoxUrl= wp.url.addQueryArgs( window._wpMetaBoxUrl, { 'meta-box-loader-nonce': nonces.replace.metabox_loader_nonce } );
+					}
+
+					if ( nonces.replace._wpnonce ) {
+						$( '#_wpnonce' ).val( nonces.replace._wpnonce );
+					}
+				}
+			}
+		}).ready( function() {
+			schedule();
+		});
+	} )( jQuery );";
+	wp_add_inline_script( 'heartbeat', $script );
+
 	// Reset meta box data.
 	$wp_meta_boxes = $_original_meta_boxes;
 }
diff --git a/tests/phpunit/tests/admin/includesPost.php b/tests/phpunit/tests/admin/includesPost.php
index eaf20d987e..2a41131a92 100644
--- a/tests/phpunit/tests/admin/includesPost.php
+++ b/tests/phpunit/tests/admin/includesPost.php
@@ -1016,4 +1016,42 @@ class Tests_Admin_IncludesPost extends WP_UnitTestCase {
 		$this->assertSame( 0, post_exists( $title, null, null, $post_type, 'draft' ) );
 		$this->assertSame( 0, post_exists( $title, null, null, 'wp_tests', $post_status ) );
 	}
+
+	/**
+	 * Test refreshed nonce for metabox loader.
+	 *
+	 * @return void
+	 */
+	public function test_user_get_refreshed_metabox_nonce() {
+
+		// Create a post by the current user.
+		wp_set_current_user( self::$editor_id );
+
+		$post_data = array(
+			'post_content' => 'Test post content',
+			'post_title'   => 'Test post title',
+			'post_excerpt' => 'Test post excerpt',
+			'post_author'  => self::$editor_id,
+			'post_status'  => 'draft',
+		);
+		$post_id   = wp_insert_post( $post_data );
+
+		// Simulate the $_POST data from the heartbeat.
+		$data = array(
+			'wp-refresh-metabox-loader-nonces' => array(
+				'post_id' => (string) $post_id,
+			),
+			'wp-refresh-post-lock'             => array(
+				'lock'    => '1658203298:1',
+				'post_id' => (string) $post_id,
+			),
+		);
+
+		// Call the function we're testing.
+		$response = wp_refresh_metabox_loader_nonces( array(), $data );
+
+		// Ensure that both nonces were created.
+		$this->assertNotEmpty( $response['wp-refresh-metabox-loader-nonces']['replace']['_wpnonce'] );
+		$this->assertNotEmpty( $response['wp-refresh-metabox-loader-nonces']['replace']['metabox_loader_nonce'] );
+	}
 }