diff --git a/internal/biz/greeter.go b/internal/biz/greeter.go
new file mode 100644
index 0000000000000000000000000000000000000000..51aeaa68ad3dcc558e7810eabd1a6f7381017e1f
--- /dev/null
+++ b/internal/biz/greeter.go
@@ -0,0 +1,45 @@
+package biz
+
+import (
+	"context"
+
+	v1 "github.com/go-kratos/kratos-layout/api/helloworld/v1"
+	"github.com/go-kratos/kratos/v2/errors"
+	"github.com/go-kratos/kratos/v2/log"
+)
+
+var (
+	// ErrUserNotFound is user not found.
+	ErrUserNotFound = errors.NotFound(v1.ErrorReason_USER_NOT_FOUND.String(), "user not found")
+)
+
+// Greeter is a Greeter model.
+type Greeter struct {
+	Hello string
+}
+
+// GreeterRepo is a Greater repo.
+type GreeterRepo interface {
+	Save(context.Context, *Greeter) (*Greeter, error)
+	Update(context.Context, *Greeter) (*Greeter, error)
+	FindByID(context.Context, int64) (*Greeter, error)
+	ListByHello(context.Context, string) ([]*Greeter, error)
+	ListAll(context.Context) ([]*Greeter, error)
+}
+
+// GreeterUsecase is a Greeter usecase.
+type GreeterUsecase struct {
+	repo GreeterRepo
+	log  *log.Helper
+}
+
+// NewGreeterUsecase new a Greeter usecase.
+func NewGreeterUsecase(repo GreeterRepo) *GreeterUsecase {
+	return &GreeterUsecase{repo: repo}
+}
+
+// CreateGreeter creates a Greeter, and returns the new Greeter.
+func (uc *GreeterUsecase) CreateGreeter(ctx context.Context, g *Greeter) (*Greeter, error) {
+	log.Infof("CreateGreeter: %v", g.Hello)
+	return uc.repo.Save(ctx, g)
+}
diff --git a/internal/data/greeter.go b/internal/data/greeter.go
new file mode 100644
index 0000000000000000000000000000000000000000..7af3138e507fbc9d74b58a524d10c3a760d0e6b5
--- /dev/null
+++ b/internal/data/greeter.go
@@ -0,0 +1,38 @@
+package data
+
+import (
+	"context"
+
+	"github.com/go-kratos/kratos-layout/internal/biz"
+)
+
+type greeterRepo struct {
+	data *Data
+}
+
+// NewGreeterRepo .
+func NewGreeterRepo(data *Data) biz.GreeterRepo {
+	return &greeterRepo{
+		data: data,
+	}
+}
+
+func (r *greeterRepo) Save(ctx context.Context, g *biz.Greeter) (*biz.Greeter, error) {
+	return g, nil
+}
+
+func (r *greeterRepo) Update(ctx context.Context, g *biz.Greeter) (*biz.Greeter, error) {
+	return g, nil
+}
+
+func (r *greeterRepo) FindByID(context.Context, int64) (*biz.Greeter, error) {
+	return nil, nil
+}
+
+func (r *greeterRepo) ListByHello(context.Context, string) ([]*biz.Greeter, error) {
+	return nil, nil
+}
+
+func (r *greeterRepo) ListAll(context.Context) ([]*biz.Greeter, error) {
+	return nil, nil
+}
diff --git a/internal/service/greeter.go b/internal/service/greeter.go
new file mode 100644
index 0000000000000000000000000000000000000000..a05ee671409ad7d43ef290c0f6350796b58fb422
--- /dev/null
+++ b/internal/service/greeter.go
@@ -0,0 +1,29 @@
+package service
+
+import (
+	"context"
+
+	v1 "github.com/go-kratos/kratos-layout/api/helloworld/v1"
+	"github.com/go-kratos/kratos-layout/internal/biz"
+)
+
+// GreeterService is a greeter service.
+type GreeterService struct {
+	v1.UnimplementedGreeterServer
+
+	uc *biz.GreeterUsecase
+}
+
+// NewGreeterService new a greeter service.
+func NewGreeterService(uc *biz.GreeterUsecase) *GreeterService {
+	return &GreeterService{uc: uc}
+}
+
+// SayHello implements helloworld.GreeterServer.
+func (s *GreeterService) SayHello(ctx context.Context, in *v1.HelloRequest) (*v1.HelloReply, error) {
+	g, err := s.uc.CreateGreeter(ctx, &biz.Greeter{Hello: in.Name})
+	if err != nil {
+		return nil, err
+	}
+	return &v1.HelloReply{Message: "Hello " + g.Hello}, nil
+}