diff --git a/optimizely/project_config.py b/optimizely/project_config.py
index 82da17c9..12fd1086 100644
--- a/optimizely/project_config.py
+++ b/optimizely/project_config.py
@@ -41,7 +41,7 @@ def __init__(self, datafile, logger, error_handler):
         """
 
         config = json.loads(datafile)
-        self._datafile = u'{}'.format(datafile)
+        self._datafile = datafile.decode('utf-8') if isinstance(datafile, bytes) else datafile
         self.logger = logger
         self.error_handler = error_handler
         self.version = config.get('version')
diff --git a/tests/test_config.py b/tests/test_config.py
index 96450368..83ebb18c 100644
--- a/tests/test_config.py
+++ b/tests/test_config.py
@@ -1011,6 +1011,19 @@ def test_to_datafile(self):
 
         self.assertEqual(expected_datafile, actual_datafile)
 
+    def test_to_datafile_from_bytes(self):
+        """ Test that to_datafile returns the expected datafile when given bytes. """
+
+        expected_datafile = json.dumps(self.config_dict_with_features)
+        bytes_datafile = bytes(expected_datafile, 'utf-8')
+
+        opt_obj = optimizely.Optimizely(bytes_datafile)
+        project_config = opt_obj.config_manager.get_config()
+
+        actual_datafile = project_config.to_datafile()
+
+        self.assertEqual(expected_datafile, actual_datafile)
+
 
 class ConfigLoggingTest(base.BaseTest):
     def setUp(self):
diff --git a/tests/test_optimizely_config.py b/tests/test_optimizely_config.py
index c37a8434..640100d7 100644
--- a/tests/test_optimizely_config.py
+++ b/tests/test_optimizely_config.py
@@ -1525,6 +1525,18 @@ def test__get_datafile(self):
 
         self.assertEqual(expected_datafile, actual_datafile)
 
+    def test__get_datafile_from_bytes(self):
+        """ Test that get_datafile returns the expected datafile when provided as bytes. """
+
+        expected_datafile = json.dumps(self.config_dict_with_features)
+        bytes_datafile = bytes(expected_datafile, 'utf-8')
+
+        opt_instance = optimizely.Optimizely(bytes_datafile)
+        opt_config = opt_instance.config_manager.optimizely_config
+        actual_datafile = opt_config.get_datafile()
+
+        self.assertEqual(expected_datafile, actual_datafile)
+
     def test__get_sdk_key(self):
         """ Test that get_sdk_key returns the expected value. """