diff --git a/packages/block-library/src/post-author/index.php b/packages/block-library/src/post-author/index.php
index dd251c2fd1c41e..21b9dde57aea44 100644
--- a/packages/block-library/src/post-author/index.php
+++ b/packages/block-library/src/post-author/index.php
@@ -30,7 +30,6 @@ function render_block_core_post_author( $attributes, $content, $block ) {
 
 	$byline  = ! empty( $attributes['byline'] ) ? $attributes['byline'] : false;
 	$classes = array_merge(
-		isset( $attributes['className'] ) ? array( $attributes['className'] ) : array(),
 		isset( $attributes['itemsJustification'] ) ? array( 'items-justified-' . $attributes['itemsJustification'] ) : array(),
 		isset( $attributes['textAlign'] ) ? array( 'has-text-align-' . $attributes['textAlign'] ) : array()
 	);