diff --git a/pubsub/setup.py b/pubsub/setup.py
index 4cc4225fce7a..b8ab933c5167 100644
--- a/pubsub/setup.py
+++ b/pubsub/setup.py
@@ -29,7 +29,7 @@
 # 'Development Status :: 5 - Production/Stable'
 release_status = "Development Status :: 4 - Beta"
 dependencies = [
-    "google-api-core[grpc] >= 1.6.0, < 2.0.0dev",
+    "google-api-core[grpc] >= 1.12.0, < 2.0.0dev",
     "grpc-google-iam-v1 >= 0.11.4, < 0.12dev",
     'enum34; python_version < "3.4"',
 ]