diff --git a/docs/data/tree-view/simple-tree-view/customization/GmailTreeView.js b/docs/data/tree-view/simple-tree-view/customization/GmailTreeView.js
index 923906321f2c..62129cad56db 100644
--- a/docs/data/tree-view/simple-tree-view/customization/GmailTreeView.js
+++ b/docs/data/tree-view/simple-tree-view/customization/GmailTreeView.js
@@ -141,7 +141,7 @@ export default function GmailTreeView() {
         endIcon: EndIcon,
       }}
       sx={{ flexGrow: 1, maxWidth: 400 }}
-      itemChildrenIndentation={28}
+      itemChildrenIndentation={16}
     >
       <CustomTreeItem itemId="1" label="All Mail" labelIcon={MailIcon} />
       <CustomTreeItem itemId="2" label="Trash" labelIcon={DeleteIcon} />