diff --git a/stable_baselines3/common/env_checker.py b/stable_baselines3/common/env_checker.py
index 116b297..6b387cc 100644
--- a/stable_baselines3/common/env_checker.py
+++ b/stable_baselines3/common/env_checker.py
@@ -380,6 +380,8 @@ def check_env(env: gym.Env, warn: bool = True, skip_render_check: bool = True) -
 
     It also optionally check that the environment is compatible with Stable-Baselines.
 
+    Note that this function eventually calls the close the environment.
+
     :param env: The Gym environment that will be checked
     :param warn: Whether to output additional warnings
         mainly related to the interaction with Stable Baselines
@@ -449,12 +451,8 @@ def check_env(env: gym.Env, warn: bool = True, skip_render_check: bool = True) -
         pass
 
     # Finally, check that the allows calling `close()` even if the environment was already closed
-    if env.spec is not None:
-        new_env = env.spec.make()
-        new_env.close()
-        try:
-            new_env.close()
-        except Exception as e:
-            warnings.warn(
-                f"Calling `env.close()` on the closed environment should be allowed, but it raised an exception: {e}"
-            )
+    env.close()
+    try:
+        env.close()
+    except Exception as e:
+        warnings.warn(f"Calling `env.close()` on the closed environment should be allowed, but it raised an exception: {e}")