diff --git a/requirements.txt b/requirements.txt
index 92f78c6..a9e1267 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,6 +1,6 @@
 # TODO(jrobbins): Update to a 2.x version of flask, which may require source
 # code changes.
-Flask==2.3.2
+Flask==3.1.3
 funcsigs==1.0.2
 Jinja2==2.11.3
 MarkupSafe==1.1.1