diff --git a/Lib/test/test_importlib/source/test_file_loader.py b/Lib/test/test_importlib/source/test_file_loader.py
index c70c5eb34ae338..5a1238f04c03c6 100644
--- a/Lib/test/test_importlib/source/test_file_loader.py
+++ b/Lib/test/test_importlib/source/test_file_loader.py
@@ -236,6 +236,7 @@ def test_unloadable(self):
                 loader.load_module('bad name')
 
     @util.writes_bytecode_files
+    @util.without_source_date_epoch
     def test_checked_hash_based_pyc(self):
         with util.create_modules('_temp') as mapping:
             source = mapping['_temp']
@@ -267,6 +268,7 @@ def test_checked_hash_based_pyc(self):
             )
 
     @util.writes_bytecode_files
+    @util.without_source_date_epoch
     def test_overridden_checked_hash_based_pyc(self):
         with util.create_modules('_temp') as mapping, \
              unittest.mock.patch('_imp.check_hash_based_pycs', 'never'):
@@ -292,6 +294,7 @@ def test_overridden_checked_hash_based_pyc(self):
             self.assertEqual(mod.state, 'old')
 
     @util.writes_bytecode_files
+    @util.without_source_date_epoch
     def test_unchecked_hash_based_pyc(self):
         with util.create_modules('_temp') as mapping:
             source = mapping['_temp']
@@ -322,6 +325,7 @@ def test_unchecked_hash_based_pyc(self):
             )
 
     @util.writes_bytecode_files
+    @util.without_source_date_epoch
     def test_overiden_unchecked_hash_based_pyc(self):
         with util.create_modules('_temp') as mapping, \
              unittest.mock.patch('_imp.check_hash_based_pycs', 'always'):
@@ -359,6 +363,25 @@ def test_overiden_unchecked_hash_based_pyc(self):
                     abc=importlib_abc, util=importlib_util)
 
 
+# Run tests with SOURCE_DATE_EPOCH set explicitly.
+class SourceDateEpochTestMeta(type(Source_SimpleTest)):
+    def __new__(mcls, name, bases, dct):
+        cls = super().__new__(mcls, name, bases, dct)
+
+        for attr in dir(cls):
+            if attr.startswith('test_'):
+                meth = getattr(cls, attr)
+                wrapper = util.with_source_date_epoch(meth)
+                setattr(cls, attr, wrapper)
+
+        return cls
+
+
+class SourceDateEpoch_SimpleTest(Source_SimpleTest,
+                                 metaclass=SourceDateEpochTestMeta):
+    pass
+
+
 class BadBytecodeTest:
 
     def import_(self, file, module_name):
@@ -617,6 +640,7 @@ def test_bad_marshal(self):
 
     # [bad timestamp]
     @util.writes_bytecode_files
+    @util.without_source_date_epoch
     def test_old_timestamp(self):
         # When the timestamp is older than the source, bytecode should be
         # regenerated.
@@ -668,6 +692,12 @@ class SourceLoaderBadBytecodeTestPEP451(
                     util=importlib_util)
 
 
+class SourceDateEpoch_SourceBadBytecodePEP451(
+        Source_SourceBadBytecodePEP451,
+        metaclass=SourceDateEpochTestMeta):
+    pass
+
+
 class SourceLoaderBadBytecodeTestPEP302(
         SourceLoaderBadBytecodeTest, BadBytecodeTestPEP302):
     pass
diff --git a/Lib/test/test_importlib/util.py b/Lib/test/test_importlib/util.py
index 196ea1c9d4dda5..28a800bdfff74f 100644
--- a/Lib/test/test_importlib/util.py
+++ b/Lib/test/test_importlib/util.py
@@ -307,6 +307,26 @@ def wrapper(*args, **kwargs):
     return wrapper
 
 
+def without_source_date_epoch(fxn):
+    """Runs function with SOURCE_DATE_EPOCH unset."""
+    @functools.wraps(fxn)
+    def wrapper(*args, **kwargs):
+        with support.EnvironmentVarGuard() as env:
+            env.unset('SOURCE_DATE_EPOCH')
+            return fxn(*args, **kwargs)
+    return wrapper
+
+
+def with_source_date_epoch(fxn):
+    """Runs function with SOURCE_DATE_EPOCH set."""
+    @functools.wraps(fxn)
+    def wrapper(*args, **kwargs):
+        with support.EnvironmentVarGuard() as env:
+            env['SOURCE_DATE_EPOCH'] = '123456789'
+            return fxn(*args, **kwargs)
+    return wrapper
+
+
 def ensure_bytecode_path(bytecode_path):
     """Ensure that the __pycache__ directory for PEP 3147 pyc file exists.
 
diff --git a/Misc/NEWS.d/next/Tests/2018-09-21-18-36-29.bpo-34022.j6a0nt.rst b/Misc/NEWS.d/next/Tests/2018-09-21-18-36-29.bpo-34022.j6a0nt.rst
new file mode 100644
index 00000000000000..bb20b0d8d9e427
--- /dev/null
+++ b/Misc/NEWS.d/next/Tests/2018-09-21-18-36-29.bpo-34022.j6a0nt.rst
@@ -0,0 +1 @@
+Unbreak importlib tests when :envvar:`SOURCE_DATE_EPOCH` is set.