diff --git a/src/frontends/lean/elaborator.h b/src/frontends/lean/elaborator.h
index cadbfd027..05222ed69 100644
--- a/src/frontends/lean/elaborator.h
+++ b/src/frontends/lean/elaborator.h
@@ -6,6 +6,7 @@ Author: Leonardo de Moura
 */
 #pragma once
 #include <utility>
+#include <vector>
 #include "util/list.h"
 #include "kernel/metavar.h"
 #include "kernel/type_checker.h"