diff --git a/ropetest/conftest.py b/ropetest/conftest.py
index 30af57e8..77d44d6c 100644
--- a/ropetest/conftest.py
+++ b/ropetest/conftest.py
@@ -105,4 +105,4 @@ def external_fixturepkg(session_venv, session_venv_python_executable):
         "ropetest-package-fixtures/external_fixturepkg/dist/external_fixturepkg-1.0.0-py3-none-any.whl",
     ])
     yield
-    check_call([sys.executable, "-m", "pip", "uninstall", "--yes", "external-fixturepkg"])
+    check_call([session_venv_python_executable, "-m", "pip", "uninstall", "--yes", "external-fixturepkg"])