diff --git a/src/wp-includes/rest-api/endpoints/class-wp-rest-comments-controller.php b/src/wp-includes/rest-api/endpoints/class-wp-rest-comments-controller.php
index a0b68759f9942..0714a9ebfb108 100644
--- a/src/wp-includes/rest-api/endpoints/class-wp-rest-comments-controller.php
+++ b/src/wp-includes/rest-api/endpoints/class-wp-rest-comments-controller.php
@@ -859,8 +859,7 @@ public function update_item( $request ) {
 			if ( is_wp_error( $prepared_args ) ) {
 				return $prepared_args;
 			}
-
-			if ( isset( $prepared_args['comment_content'] ) && empty( $prepared_args['comment_content'] ) ) {
+			if ( ! $this->check_is_comment_content_allowed( $prepared_args ) ) {
 				return new WP_Error(
 					'rest_comment_content_invalid',
 					__( 'Invalid comment content.' ),
@@ -1903,6 +1902,10 @@ public function check_comment_author_email( $value, $request, $param ) {
 	 * @return bool True if the content is allowed, false otherwise.
 	 */
 	protected function check_is_comment_content_allowed( $prepared_comment ) {
+		if ( ! isset( $prepared_comment['comment_content'] ) ) {
+			return true;
+		}
+
 		$check = wp_parse_args(
 			$prepared_comment,
 			array(
diff --git a/tests/phpunit/tests/rest-api/rest-comments-controller.php b/tests/phpunit/tests/rest-api/rest-comments-controller.php
index 0bfe4e778d870..90192a2e247a0 100644
--- a/tests/phpunit/tests/rest-api/rest-comments-controller.php
+++ b/tests/phpunit/tests/rest-api/rest-comments-controller.php
@@ -2493,6 +2493,30 @@ public function test_update_item_no_content() {
 		$this->assertErrorResponse( 'rest_comment_content_invalid', $response, 400 );
 	}
 
+	/**
+	 * @ticket 64049
+	 */
+	public function test_update_item_no_content_allow_empty_comment_filter() {
+		$post_id = self::factory()->post->create();
+
+		wp_set_current_user( self::$admin_id );
+
+		$request = new WP_REST_Request( 'PUT', sprintf( '/wp/v2/comments/%d', self::$approved_id ) );
+		$request->set_param( 'author_email', 'another@email.com' );
+
+		// Sending a request without content is fine.
+		$response = rest_get_server()->dispatch( $request );
+		$this->assertSame( 200, $response->get_status() );
+
+		// Sending a request with empty comment is not fine.
+		$request->set_param( 'author_email', 'yetanother@email.com' );
+		$request->set_param( 'content', '' );
+		add_filter( 'allow_empty_comment', '__return_true' );
+		$response = rest_get_server()->dispatch( $request );
+		remove_filter( 'allow_empty_comment', '__return_true' );
+		$this->assertSame( 200, $response->get_status() );
+	}
+
 	public function test_update_item_no_change() {
 		$comment = get_comment( self::$approved_id );