diff --git a/call_test.go b/call_test.go
index d57d01e4..df936400 100644
--- a/call_test.go
+++ b/call_test.go
@@ -32,8 +32,8 @@ import (
 	"golang.org/x/net/context"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/internal/leakcheck"
+	"google.golang.org/grpc/internal/transport"
 	"google.golang.org/grpc/status"
-	"google.golang.org/grpc/transport"
 )
 
 var (
diff --git a/clientconn.go b/clientconn.go
index e5568feb..c8374b15 100644
--- a/clientconn.go
+++ b/clientconn.go
@@ -41,13 +41,13 @@ import (
 	"google.golang.org/grpc/internal/backoff"
 	"google.golang.org/grpc/internal/channelz"
 	"google.golang.org/grpc/internal/envconfig"
+	"google.golang.org/grpc/internal/transport"
 	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/resolver"
 	_ "google.golang.org/grpc/resolver/dns"         // To register dns resolver.
 	_ "google.golang.org/grpc/resolver/passthrough" // To register passthrough resolver.
 	"google.golang.org/grpc/stats"
 	"google.golang.org/grpc/status"
-	"google.golang.org/grpc/transport"
 )
 
 const (
diff --git a/go16.go b/go16.go
index 535ee935..0e3a029f 100644
--- a/go16.go
+++ b/go16.go
@@ -28,8 +28,8 @@ import (
 
 	"golang.org/x/net/context"
 	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/internal/transport"
 	"google.golang.org/grpc/status"
-	"google.golang.org/grpc/transport"
 )
 
 // dialContext connects to the address on the named network.
diff --git a/go17.go b/go17.go
index ec676a93..486dd73f 100644
--- a/go17.go
+++ b/go17.go
@@ -29,8 +29,8 @@ import (
 
 	netctx "golang.org/x/net/context"
 	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/internal/transport"
 	"google.golang.org/grpc/status"
-	"google.golang.org/grpc/transport"
 )
 
 // dialContext connects to the address on the named network.
diff --git a/transport/bdp_estimator.go b/internal/transport/bdp_estimator.go
similarity index 100%
rename from transport/bdp_estimator.go
rename to internal/transport/bdp_estimator.go
diff --git a/transport/controlbuf.go b/internal/transport/controlbuf.go
similarity index 100%
rename from transport/controlbuf.go
rename to internal/transport/controlbuf.go
diff --git a/transport/defaults.go b/internal/transport/defaults.go
similarity index 100%
rename from transport/defaults.go
rename to internal/transport/defaults.go
diff --git a/transport/flowcontrol.go b/internal/transport/flowcontrol.go
similarity index 100%
rename from transport/flowcontrol.go
rename to internal/transport/flowcontrol.go
diff --git a/transport/go16.go b/internal/transport/go16.go
similarity index 100%
rename from transport/go16.go
rename to internal/transport/go16.go
diff --git a/transport/go17.go b/internal/transport/go17.go
similarity index 100%
rename from transport/go17.go
rename to internal/transport/go17.go
diff --git a/transport/handler_server.go b/internal/transport/handler_server.go
similarity index 100%
rename from transport/handler_server.go
rename to internal/transport/handler_server.go
diff --git a/transport/handler_server_test.go b/internal/transport/handler_server_test.go
similarity index 100%
rename from transport/handler_server_test.go
rename to internal/transport/handler_server_test.go
diff --git a/transport/http2_client.go b/internal/transport/http2_client.go
similarity index 100%
rename from transport/http2_client.go
rename to internal/transport/http2_client.go
diff --git a/transport/http2_server.go b/internal/transport/http2_server.go
similarity index 100%
rename from transport/http2_server.go
rename to internal/transport/http2_server.go
diff --git a/transport/http_util.go b/internal/transport/http_util.go
similarity index 100%
rename from transport/http_util.go
rename to internal/transport/http_util.go
diff --git a/transport/http_util_test.go b/internal/transport/http_util_test.go
similarity index 100%
rename from transport/http_util_test.go
rename to internal/transport/http_util_test.go
diff --git a/transport/log.go b/internal/transport/log.go
similarity index 100%
rename from transport/log.go
rename to internal/transport/log.go
diff --git a/transport/transport.go b/internal/transport/transport.go
similarity index 99%
rename from transport/transport.go
rename to internal/transport/transport.go
index e724ca93..4ae3a5cb 100644
--- a/transport/transport.go
+++ b/internal/transport/transport.go
@@ -19,7 +19,7 @@
 // Package transport defines and implements message oriented communication
 // channel to complete various transactions (e.g., an RPC).  It is meant for
 // grpc-internal usage and is not intended to be imported directly by users.
-package transport // externally used as import "google.golang.org/grpc/transport"
+package transport
 
 import (
 	"errors"
diff --git a/transport/transport_test.go b/internal/transport/transport_test.go
similarity index 100%
rename from transport/transport_test.go
rename to internal/transport/transport_test.go
diff --git a/picker_wrapper.go b/picker_wrapper.go
index 46b95ad5..76cc456a 100644
--- a/picker_wrapper.go
+++ b/picker_wrapper.go
@@ -27,8 +27,8 @@ import (
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/grpclog"
 	"google.golang.org/grpc/internal/channelz"
+	"google.golang.org/grpc/internal/transport"
 	"google.golang.org/grpc/status"
-	"google.golang.org/grpc/transport"
 )
 
 // pickerWrapper is a wrapper of balancer.Picker. It blocks on certain pick
diff --git a/picker_wrapper_test.go b/picker_wrapper_test.go
index d455286d..34c6c891 100644
--- a/picker_wrapper_test.go
+++ b/picker_wrapper_test.go
@@ -29,7 +29,7 @@ import (
 	"google.golang.org/grpc/connectivity"
 	_ "google.golang.org/grpc/grpclog/glogger"
 	"google.golang.org/grpc/internal/leakcheck"
-	"google.golang.org/grpc/transport"
+	"google.golang.org/grpc/internal/transport"
 )
 
 const goroutineCount = 5
diff --git a/rpc_util.go b/rpc_util.go
index 836944f5..cfd81159 100644
--- a/rpc_util.go
+++ b/rpc_util.go
@@ -36,11 +36,11 @@ import (
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/encoding"
 	"google.golang.org/grpc/encoding/proto"
+	"google.golang.org/grpc/internal/transport"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
 	"google.golang.org/grpc/stats"
 	"google.golang.org/grpc/status"
-	"google.golang.org/grpc/transport"
 )
 
 // Compressor defines the interface gRPC uses to compress a message.
diff --git a/rpc_util_test.go b/rpc_util_test.go
index f28cff23..6fbebdc3 100644
--- a/rpc_util_test.go
+++ b/rpc_util_test.go
@@ -30,9 +30,9 @@ import (
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/encoding"
 	protoenc "google.golang.org/grpc/encoding/proto"
+	"google.golang.org/grpc/internal/transport"
 	"google.golang.org/grpc/status"
 	perfpb "google.golang.org/grpc/test/codec_perf"
-	"google.golang.org/grpc/transport"
 )
 
 type fullReader struct {
diff --git a/server.go b/server.go
index a85297bc..3f64e219 100644
--- a/server.go
+++ b/server.go
@@ -45,12 +45,12 @@ import (
 	"google.golang.org/grpc/grpclog"
 	"google.golang.org/grpc/internal"
 	"google.golang.org/grpc/internal/channelz"
+	"google.golang.org/grpc/internal/transport"
 	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/stats"
 	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/tap"
-	"google.golang.org/grpc/transport"
 )
 
 const (
diff --git a/server_test.go b/server_test.go
index 77e40b02..11ce8673 100644
--- a/server_test.go
+++ b/server_test.go
@@ -27,7 +27,7 @@ import (
 
 	"golang.org/x/net/context"
 	"google.golang.org/grpc/internal/leakcheck"
-	"google.golang.org/grpc/transport"
+	"google.golang.org/grpc/internal/transport"
 )
 
 type emptyServiceServer interface{}
diff --git a/stream.go b/stream.go
index 2c82eeb8..70b19848 100644
--- a/stream.go
+++ b/stream.go
@@ -34,10 +34,10 @@ import (
 	"google.golang.org/grpc/grpclog"
 	"google.golang.org/grpc/internal/channelz"
 	"google.golang.org/grpc/internal/grpcrand"
+	"google.golang.org/grpc/internal/transport"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/stats"
 	"google.golang.org/grpc/status"
-	"google.golang.org/grpc/transport"
 )
 
 // StreamHandler defines the handler called by gRPC server to complete the
diff --git a/vet.sh b/vet.sh
index 44525dc8..44a310e5 100755
--- a/vet.sh
+++ b/vet.sh
@@ -78,7 +78,7 @@ fi
 
 # TODO(menghanl): fix errors in transport_test.
 staticcheck -ignore '
-google.golang.org/grpc/transport/transport_test.go:SA2002
+google.golang.org/grpc/internal/transport/transport_test.go:SA2002
 google.golang.org/grpc/benchmark/benchmain/main.go:SA1019
 google.golang.org/grpc/stats/stats_test.go:SA1019
 google.golang.org/grpc/test/end2end_test.go:SA1019