diff --git a/src/wp-includes/author-template.php b/src/wp-includes/author-template.php
index 2280487d09..c795e1216a 100644
--- a/src/wp-includes/author-template.php
+++ b/src/wp-includes/author-template.php
@@ -197,7 +197,7 @@ function get_the_author_posts() {
 	if ( ! $post ) {
 		return 0;
 	}
-	return count_user_posts( $post->post_author );
+	return count_user_posts( $post->post_author, $post->post_type );
 }
 
 /**
diff --git a/tests/phpunit/tests/user/author.php b/tests/phpunit/tests/user/author.php
index 8646a9ba42..71fa99a37e 100644
--- a/tests/phpunit/tests/user/author.php
+++ b/tests/phpunit/tests/user/author.php
@@ -82,4 +82,21 @@ class Tests_User_Author extends WP_UnitTestCase {
 		$GLOBALS['post'] = $this->post_id;
 		$this->assertEquals( 1, get_the_author_posts() );
 	}
+
+	/**
+	 * @ticket 30904
+	 */
+	function test_get_the_author_posts_with_custom_post_type() {
+		register_post_type( 'wptests_pt' );
+
+		$cpt_ids = $this->factory->post->create_many( 2, array(
+			'post_author' => $this->author_id,
+			'post_type'   => 'wptests_pt',
+		) );
+		$GLOBALS['post'] = $cpt_ids[0];
+
+		$this->assertEquals( 2, get_the_author_posts() );
+
+		_unregister_post_type( 'wptests_pt' );
+	}
 }