diff --git a/haskell/repositories.bzl b/haskell/repositories.bzl
index 05da35318..d6932387d 100644
--- a/haskell/repositories.bzl
+++ b/haskell/repositories.bzl
@@ -129,10 +129,10 @@ def rules_haskell_dependencies():
     maybe(
         http_archive,
         name = "com_google_protobuf",
-        sha256 = "7c3ebd7aaedd86fa5dc479a0fda803f602caaf78d8aff7ce83b89e1b8ae7442a",
-        strip_prefix = "protobuf-28.3",
+        sha256 = "a83103b7ed3afaeedee9a212c8f65825444f58144f5e075b73c83f2b4ff27b62",
+        strip_prefix = "protobuf-34.1",
         urls = [
-            "https://github.com/protocolbuffers/protobuf/archive/refs/tags/v28.3.tar.gz",
+            "https://github.com/protocolbuffers/protobuf/archive/refs/tags/v34.1.tar.gz",
         ],
         patches = [
             # see https://github.com/protocolbuffers/protobuf/issues/16844
diff --git a/rules_haskell_tests/MODULE.bazel b/rules_haskell_tests/MODULE.bazel
index 393209125..fb40f3676 100644
--- a/rules_haskell_tests/MODULE.bazel
+++ b/rules_haskell_tests/MODULE.bazel
@@ -81,7 +81,7 @@ bazel_dep(
 )
 bazel_dep(
     name = "protobuf",
-    version = "28.3",
+    version = "34.1",
     repo_name = "com_google_protobuf",
 )
 single_version_override(