diff --git a/tempest/common/rest_client.py b/tempest/common/rest_client.py
index 33128a9..9273437 100644
--- a/tempest/common/rest_client.py
+++ b/tempest/common/rest_client.py
@@ -18,6 +18,7 @@
 import json
 from lxml import etree
 import re
+import string
 import time
 
 import jsonschema
@@ -295,9 +296,11 @@
                     req_url,
                     secs,
                     str(req_headers),
-                    str(req_body)[:2048],
+                    filter(lambda x: x in string.printable,
+                           str(req_body)[:2048]),
                     str(resp),
-                    str(resp_body)[:2048]),
+                    filter(lambda x: x in string.printable,
+                           str(resp_body)[:2048])),
                 extra=extra)
 
     def _parse_resp(self, body):