diff --git a/lib/tempest b/lib/tempest
index b232f24..ec2949a 100644
--- a/lib/tempest
+++ b/lib/tempest
@@ -779,7 +779,12 @@
 # install_tempest() - Collect source and prepare
 function install_tempest {
     git_clone $TEMPEST_REPO $TEMPEST_DIR $TEMPEST_BRANCH
-    pip_install 'tox!=2.8.0'
+    # NOTE(gmann): Pinning tox<4.0.0 for stable/zed and lower. Tox 4.0.0
+    # released after zed was released and has some incompatible changes
+    # and it is ok not to fix the issues caused by tox 4.0.0 in stable
+    # beanches jobs. We can continue testing the stable/zed and lower
+    # branches with tox<4.0.0
+    pip_install 'tox!=2.8.0,<4.0.0'
     pushd $TEMPEST_DIR
     # NOTE(gmann): checkout the TEMPEST_BRANCH in case TEMPEST_BRANCH
     # is tag name not master. git_clone would not checkout tag because