diff --git a/moto/glacier/responses.py b/moto/glacier/responses.py
index fd3bf3525..37cbdc4c9 100644
--- a/moto/glacier/responses.py
+++ b/moto/glacier/responses.py
@@ -123,7 +123,7 @@ class GlacierResponse(_TemplateEnvironmentMixin):
                 "Marker": None,
             })
         elif method == 'POST':
-            json_body = json.loads(body)
+            json_body = json.loads(body.decode("utf-8"))
             archive_id = json_body['ArchiveId']
             job_id = self.backend.initiate_job(vault_name, archive_id)
             headers['x-amz-job-id'] = job_id
diff --git a/tests/test_glacier/test_glacier_archives.py b/tests/test_glacier/test_glacier_archives.py
index 72b2afb16..6a139a91c 100644
--- a/tests/test_glacier/test_glacier_archives.py
+++ b/tests/test_glacier/test_glacier_archives.py
@@ -10,7 +10,7 @@ from moto import mock_glacier
 @mock_glacier
 def test_create_and_delete_archive():
     the_file = NamedTemporaryFile(delete=False)
-    the_file.write("some stuff")
+    the_file.write(b"some stuff")
     the_file.close()
 
     conn = boto.glacier.connect_to_region("us-west-2")