diff --git a/.github/workflows/ci-protobuf.yml b/.github/workflows/ci-protobuf.yml
index 06b0d299..f3ef5eda 100644
--- a/.github/workflows/ci-protobuf.yml
+++ b/.github/workflows/ci-protobuf.yml
@@ -29,7 +29,7 @@ jobs:
           # pinned here to prevent unexpected differences. Follow the
           # https://github.com/protocolbuffers/protobuf repository for protoc
           # release updates.
-          version: '25.1'
+          version: '26.1'
       - run: go mod download
       - run: make tools
       - run: make protoc
diff --git a/go.mod b/go.mod
index d5e55834..ad32a022 100644
--- a/go.mod
+++ b/go.mod
@@ -14,7 +14,7 @@ require (
 	github.com/mitchellh/go-testing-interface v1.14.1
 	github.com/vmihailenco/msgpack/v5 v5.4.1
 	google.golang.org/grpc v1.63.2
-	google.golang.org/protobuf v1.33.0
+	google.golang.org/protobuf v1.34.0
 )
 
 require (
diff --git a/go.sum b/go.sum
index 64559510..8d264f25 100644
--- a/go.sum
+++ b/go.sum
@@ -59,8 +59,8 @@ google.golang.org/genproto/googleapis/rpc v0.0.0-20240227224415-6ceb2ff114de h1:
 google.golang.org/genproto/googleapis/rpc v0.0.0-20240227224415-6ceb2ff114de/go.mod h1:H4O17MA/PE9BsGx3w+a+W2VOLLD1Qf7oJneAoU6WktY=
 google.golang.org/grpc v1.63.2 h1:MUeiw1B2maTVZthpU5xvASfTh3LDbxHd6IJ6QQVU+xM=
 google.golang.org/grpc v1.63.2/go.mod h1:WAX/8DgncnokcFUldAxq7GeB5DXHDbMF+lLvDomNkRA=
-google.golang.org/protobuf v1.33.0 h1:uNO2rsAINq/JlFpSdYEKIZ0uKD/R9cpdv0T+yoGwGmI=
-google.golang.org/protobuf v1.33.0/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=
+google.golang.org/protobuf v1.34.0 h1:Qo/qEd2RZPCf2nKuorzksSknv0d3ERwp1vFG38gSmH4=
+google.golang.org/protobuf v1.34.0/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
diff --git a/tfprotov5/internal/tfplugin5/tfplugin5.pb.go b/tfprotov5/internal/tfplugin5/tfplugin5.pb.go
index e10c839b..c37d24e8 100644
--- a/tfprotov5/internal/tfplugin5/tfplugin5.pb.go
+++ b/tfprotov5/internal/tfplugin5/tfplugin5.pb.go
@@ -22,8 +22,8 @@
 
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // versions:
-// 	protoc-gen-go v1.33.0
-// 	protoc        v4.25.1
+// 	protoc-gen-go v1.34.0
+// 	protoc        v5.26.1
 // source: tfplugin5.proto
 
 package tfplugin5
diff --git a/tfprotov5/internal/tfplugin5/tfplugin5_grpc.pb.go b/tfprotov5/internal/tfplugin5/tfplugin5_grpc.pb.go
index fc016846..053284f6 100644
--- a/tfprotov5/internal/tfplugin5/tfplugin5_grpc.pb.go
+++ b/tfprotov5/internal/tfplugin5/tfplugin5_grpc.pb.go
@@ -23,7 +23,7 @@
 // Code generated by protoc-gen-go-grpc. DO NOT EDIT.
 // versions:
 // - protoc-gen-go-grpc v1.3.0
-// - protoc             v4.25.1
+// - protoc             v5.26.1
 // source: tfplugin5.proto
 
 package tfplugin5
diff --git a/tfprotov6/internal/tfplugin6/tfplugin6.pb.go b/tfprotov6/internal/tfplugin6/tfplugin6.pb.go
index 9016dfe4..158d02d0 100644
--- a/tfprotov6/internal/tfplugin6/tfplugin6.pb.go
+++ b/tfprotov6/internal/tfplugin6/tfplugin6.pb.go
@@ -22,8 +22,8 @@
 
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // versions:
-// 	protoc-gen-go v1.33.0
-// 	protoc        v4.25.1
+// 	protoc-gen-go v1.34.0
+// 	protoc        v5.26.1
 // source: tfplugin6.proto
 
 package tfplugin6
diff --git a/tfprotov6/internal/tfplugin6/tfplugin6_grpc.pb.go b/tfprotov6/internal/tfplugin6/tfplugin6_grpc.pb.go
index 3ae64b46..25331588 100644
--- a/tfprotov6/internal/tfplugin6/tfplugin6_grpc.pb.go
+++ b/tfprotov6/internal/tfplugin6/tfplugin6_grpc.pb.go
@@ -23,7 +23,7 @@
 // Code generated by protoc-gen-go-grpc. DO NOT EDIT.
 // versions:
 // - protoc-gen-go-grpc v1.3.0
-// - protoc             v4.25.1
+// - protoc             v5.26.1
 // source: tfplugin6.proto
 
 package tfplugin6