diff --git a/datafusion/optimizer/src/analyzer/subquery.rs b/datafusion/optimizer/src/analyzer/subquery.rs
index c36a74c328bd..9fee97529cb1 100644
--- a/datafusion/optimizer/src/analyzer/subquery.rs
+++ b/datafusion/optimizer/src/analyzer/subquery.rs
@@ -231,6 +231,7 @@ fn check_inner_plan(
                 Ok(())
             }
         },
+        LogicalPlan::Extension(_) => Ok(()),
         _ => Err(DataFusionError::Plan(
             "Unsupported operator in the subquery plan.".to_string(),
         )),