diff --git a/pyproject.toml b/pyproject.toml
index 0d92c66..3ca18a1 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -10,7 +10,7 @@ requires = [
   # sure the code is generated using the minimum supported versions, as older
   # versions can't work with code that was generated with newer versions.
   # https://protobuf.dev/support/cross-version-runtime-guarantee/#backwards
-  "protobuf == 6.32.1",
+  "protobuf == 6.33.5",
   "grpcio-tools == 1.72.1",
   "grpcio == 1.72.1",
 ]