diff --git a/src/sage/all.py b/src/sage/all.py
index b58640c6756..3d144381cf6 100644
--- a/src/sage/all.py
+++ b/src/sage/all.py
@@ -102,6 +102,11 @@
 # However, be sure to keep OUR deprecation warnings
 warnings.filterwarnings('default', category=DeprecationWarning,
     message=r'[\s\S]*See https\?://trac\.sagemath\.org/[0-9]* for details.')
+
+# Ignore Python 3.9 deprecation warnings
+warnings.filterwarnings('ignore', category=DeprecationWarning,
+    module='.*ast')
+
 ################ end setup warnings ###############################