diff --git a/tools/pip-requires b/tools/pip-requires
index 71ae740d1..24697711e 100644
--- a/tools/pip-requires
+++ b/tools/pip-requires
@@ -1,6 +1,6 @@
 argparse
 iso8601>=0.1.4
-prettytable
+prettytable>=0.6,<0.8
 requests>=0.8.8
 simplejson
 oslo.config>=1.1.0