diff --git a/requirements.txt b/requirements.txt
index d06abcd..0f6894f 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -81,7 +81,7 @@ python-dateutil==2.7.3
 python-gflags==3.1.2
 pytz==2018.5
 PyWavelets==0.5.2
-PyYAML==3.13
+PyYAML==5.4
 pyzmq==17.1.2
 qtconsole==4.4.3
 requests==2.18.4
diff --git a/requirements2.1.txt b/requirements2.1.txt
index a87f02d..078ed28 100644
--- a/requirements2.1.txt
+++ b/requirements2.1.txt
@@ -70,7 +70,7 @@ pyparsing==2.3.1
 python-dateutil==2.8.0
 pytools==2019.1.1
 pytz==2019.1
-PyYAML==5.1
+PyYAML==5.4
 pyzmq==18.0.1
 requests==2.21.0
 requests-oauthlib==1.2.0