diff --git a/test/core/test_util/BUILD b/test/core/test_util/BUILD
index 68466953ce96f..1e3367ffae31a 100644
--- a/test/core/test_util/BUILD
+++ b/test/core/test_util/BUILD
@@ -462,6 +462,7 @@ grpc_cc_library(
     name = "fuzz_config_vars_helpers",
     srcs = ["fuzz_config_vars_helpers.cc"],
     hdrs = ["fuzz_config_vars_helpers.h"],
+    testonly = 1,
     external_deps = [
         "absl/strings",
         "fuzztest",