diff --git a/packages/edit-site/src/components/editor/index.js b/packages/edit-site/src/components/editor/index.js
index 434554bbda7e82..2eac14bcc37034 100644
--- a/packages/edit-site/src/components/editor/index.js
+++ b/packages/edit-site/src/components/editor/index.js
@@ -1,7 +1,7 @@
 /**
  * WordPress dependencies
  */
-import { useMemo } from '@wordpress/element';
+import { useMemo, useEffect } from '@wordpress/element';
 import { useSelect, useDispatch } from '@wordpress/data';
 import { Notice } from '@wordpress/components';
 import { EntityProvider } from '@wordpress/core-data';
@@ -102,6 +102,7 @@ export default function Editor() {
 		};
 	}, [] );
 	const { setEditedPostContext } = useDispatch( editSiteStore );
+	const { enableComplementaryArea } = useDispatch( interfaceStore );
 
 	const isViewMode = canvasMode === 'view';
 	const isEditMode = canvasMode === 'edit';
@@ -148,6 +149,19 @@ export default function Editor() {
 		);
 	}
 
+	useEffect(
+		function openGlobalStylesOnLoad() {
+			const searchParams = new URLSearchParams( window.location.search );
+			if ( searchParams.get( 'styles' ) === 'open' ) {
+				enableComplementaryArea(
+					'core/edit-site',
+					'edit-site/global-styles'
+				);
+			}
+		},
+		[ enableComplementaryArea ]
+	);
+
 	// Only announce the title once the editor is ready to prevent "Replace"
 	// action in <URlQueryController> from double-announcing.
 	useTitle( hasLoadedPost && title );