diff --git a/packages/google-cloud-kms/setup.py b/packages/google-cloud-kms/setup.py
index fd3f3f00c119..446d1d70f05c 100644
--- a/packages/google-cloud-kms/setup.py
+++ b/packages/google-cloud-kms/setup.py
@@ -26,8 +26,8 @@
 dependencies = [
     "google-api-core[grpc] >= 1.32.0, <3.0.0dev,!=2.0.*,!=2.1.*,!=2.2.*,!=2.3.*,!=2.4.*,!=2.5.*,!=2.6.*,!=2.7.*",
     "grpc-google-iam-v1 >=0.12.4, <1.0.0dev",
-    "proto-plus >= 1.15.0, <2.0.0dev",
-    "protobuf >= 3.19.0, <4.0.0dev",
+    "proto-plus >= 1.22.0, <2.0.0dev",
+    "protobuf >= 3.19.0, <5.0.0dev",
 ]
 
 extras = {"libcst": "libcst >= 0.2.5"}
diff --git a/packages/google-cloud-kms/testing/constraints-3.7.txt b/packages/google-cloud-kms/testing/constraints-3.7.txt
index 39a7c58e1e8c..ed0460d8711c 100644
--- a/packages/google-cloud-kms/testing/constraints-3.7.txt
+++ b/packages/google-cloud-kms/testing/constraints-3.7.txt
@@ -7,6 +7,6 @@
 # Then this file should have foo==1.14.0
 google-api-core==1.32.0
 grpc-google-iam-v1==0.12.4
-proto-plus==1.15.0
+proto-plus==1.22.0
 libcst==0.2.5
 protobuf==3.19.0