diff --git a/news/9156.bugfix.rst b/news/9156.bugfix.rst
new file mode 100644
index 00000000000..9b433fae2fc
--- /dev/null
+++ b/news/9156.bugfix.rst
@@ -0,0 +1 @@
+Fix ResourceWarning in VCS subprocesses
diff --git a/src/pip/_internal/vcs/versioncontrol.py b/src/pip/_internal/vcs/versioncontrol.py
index 219f7967319..6724dcc697d 100644
--- a/src/pip/_internal/vcs/versioncontrol.py
+++ b/src/pip/_internal/vcs/versioncontrol.py
@@ -150,6 +150,8 @@ def call_subprocess(
     finally:
         if proc.stdout:
             proc.stdout.close()
+        if proc.stderr:
+            proc.stderr.close()
 
     proc_had_error = (
         proc.returncode and proc.returncode not in extra_ok_returncodes