diff --git a/Lib/test/test_sys_settrace.py b/Lib/test/test_sys_settrace.py
--- a/Lib/test/test_sys_settrace.py
+++ b/Lib/test/test_sys_settrace.py
@@ -251,6 +251,7 @@
     def setUp(self):
         self.using_gc = gc.isenabled()
         gc.disable()
+        self.addCleanup(sys.settrace, sys.gettrace())
 
     def tearDown(self):
         if self.using_gc:
@@ -389,6 +390,9 @@
 
 
 class RaisingTraceFuncTestCase(unittest.TestCase):
+    def setUp(self):
+        self.addCleanup(sys.settrace, sys.gettrace())
+
     def trace(self, frame, event, arg):
         """A trace function that raises an exception in response to a
         specific trace event."""
@@ -688,6 +692,9 @@
 
 
 class JumpTestCase(unittest.TestCase):
+    def setUp(self):
+        self.addCleanup(sys.settrace, sys.gettrace())
+
     def compare_jump_output(self, expected, received):
         if received != expected:
             self.fail( "Outputs don't match:\n" +