diff --git a/tools/build/bazel/protobuf_workspace.bzl b/tools/build/bazel/protobuf_workspace.bzl
index ebfde6b..98e31be 100644
--- a/tools/build/bazel/protobuf_workspace.bzl
+++ b/tools/build/bazel/protobuf_workspace.bzl
@@ -1,7 +1,7 @@
 load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
 
-PROTOBUF_VERSION = "3.8.0"
-SHA = "1e622ce4b84b88b6d2cdf1db38d1a634fe2392d74f0b7b74ff98f3a51838ee53"
+PROTOBUF_VERSION = "3.9.0"
+SHA = "8eb5ca331ab8ca0da2baea7fc0607d86c46c80845deca57109a5d637ccb93bb4"
 
 def generate_protobuf():
     http_archive(