diff --git a/lower-constraints.txt b/lower-constraints.txt
index fc3e7c8..62432b8 100644
--- a/lower-constraints.txt
+++ b/lower-constraints.txt
@@ -1,5 +1,5 @@
 docutils==0.11
 dulwich==0.15.0
-PyYAML==3.10.0
+PyYAML==5.3.1
 Sphinx==2.0.0
 stestr==2.1.0
diff --git a/requirements.txt b/requirements.txt
index ddc0705..5486a45 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,6 +3,6 @@
 # process, which may cause wedges in the gate later.
 
 pbr
-PyYAML>=3.10
+PyYAML>=5.3.1
 dulwich>=0.15.0  # Apache-2.0
 packaging>=20.4