diff --git a/dataproc/requirements.txt b/dataproc/requirements.txt
index f39bf65a8b36..a54880f15598 100644
--- a/dataproc/requirements.txt
+++ b/dataproc/requirements.txt
@@ -1,4 +1,4 @@
-grpcio>=1.2.0
+grpcio==1.27.1
 google-auth==1.10.0
 google-auth-httplib2==0.0.3
 google-cloud==0.34.0
diff --git a/endpoints/bookstore-grpc-transcoding/requirements.txt b/endpoints/bookstore-grpc-transcoding/requirements.txt
index e7487cf5b3bf..f86694ccf046 100644
--- a/endpoints/bookstore-grpc-transcoding/requirements.txt
+++ b/endpoints/bookstore-grpc-transcoding/requirements.txt
@@ -1,5 +1,5 @@
-grpcio>=1.10.0
-grpcio-tools>=1.10.0
-google-auth>=1.4.1
-six>=1.11
-googleapis-common-protos>=1.5.3
+grpcio==1.27.1
+grpcio-tools==1.27.1
+google-auth==1.11.0
+six==1.14.0
+googleapis-common-protos==1.51.0
diff --git a/endpoints/bookstore-grpc/requirements.txt b/endpoints/bookstore-grpc/requirements.txt
index e1c139acee88..8317e36bc18e 100644
--- a/endpoints/bookstore-grpc/requirements.txt
+++ b/endpoints/bookstore-grpc/requirements.txt
@@ -1,4 +1,4 @@
-grpcio>=1.10.0
-grpcio-tools>=1.10.0
-google-auth>=1.4.1
-six>=1.11
+grpcio==1.27.1
+grpcio-tools==1.27.1
+google-auth==1.11.1
+six==1.14.0