diff --git a/Lib/test/test_warnings.py b/Lib/test/test_warnings.py
--- a/Lib/test/test_warnings.py
+++ b/Lib/test/test_warnings.py
@@ -13,7 +13,11 @@
 import warnings as original_warnings
 
 py_warnings = support.import_fresh_module('warnings', blocked=['_warnings'])
+
+# Issue #18383: the 'sys.warnoptions' are inserted again on reload
+nfilters = len(original_warnings.filters)
 c_warnings = support.import_fresh_module('warnings', fresh=['_warnings'])
+del original_warnings.filters[:-nfilters]
 
 @contextmanager
 def warnings_state(module):