diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index be7232e5a..20b995444 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -535,8 +535,7 @@ endif()
 add_custom_target(
   memcheck
   COMMAND
-    PYBIND11_TESTING_WITH_VALGRIND=1
-    PYTHONMALLOC=malloc
+    -E env PYBIND11_TESTING_WITH_VALGRIND=1 PYTHONMALLOC=malloc
     valgrind
     --leak-check=full
     --show-leak-kinds=definite,indirect