diff --git a/packages/core/upload/admin/src/components/SelectTree/Option.js b/packages/core/upload/admin/src/components/SelectTree/Option.js
index 353c086e4f..6a49b2f5e0 100644
--- a/packages/core/upload/admin/src/components/SelectTree/Option.js
+++ b/packages/core/upload/admin/src/components/SelectTree/Option.js
@@ -55,7 +55,7 @@ Option.propTypes = {
   onToggle: PropTypes.func.isRequired,
   selectProps: PropTypes.shape({
     maxDisplayDepth: PropTypes.number,
-    openValues: PropTypes.oneOfType([PropTypes.string, PropTypes.number]),
+    openValues: PropTypes.arrayOf(PropTypes.oneOfType([PropTypes.string, PropTypes.number])),
     onOptionToggle: PropTypes.func,
   }).isRequired,
 };