diff --git a/make/photon/db/registry.sql b/make/photon/db/registry.sql
index 023ef70ec..17dbf9fa9 100644
--- a/make/photon/db/registry.sql
+++ b/make/photon/db/registry.sql
@@ -278,7 +278,7 @@ create table harbor_label (
  creation_time timestamp default CURRENT_TIMESTAMP,
  update_time timestamp default CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP,
  PRIMARY KEY(id),
- CONSTRAINT unique_name_and_scope UNIQUE (name,scope)
+ CONSTRAINT unique_label UNIQUE (name,scope, project_id)
  );
 
 create table harbor_resource_label (
diff --git a/make/photon/db/registry_sqlite.sql b/make/photon/db/registry_sqlite.sql
index c6e4ed2e9..722a58d08 100644
--- a/make/photon/db/registry_sqlite.sql
+++ b/make/photon/db/registry_sqlite.sql
@@ -260,7 +260,7 @@ create table harbor_label (
  project_id int,
  creation_time timestamp default CURRENT_TIMESTAMP,
  update_time timestamp default CURRENT_TIMESTAMP,
- UNIQUE(name, scope)
+ UNIQUE(name, scope, project_id)
  );
 
 create table harbor_resource_label (
diff --git a/src/common/dao/label_test.go b/src/common/dao/label_test.go
index 60b389e1b..d6c0f1d49 100644
--- a/src/common/dao/label_test.go
+++ b/src/common/dao/label_test.go
@@ -25,8 +25,9 @@ import (
 )
 
 func TestMethodsOfLabel(t *testing.T) {
+	labelName := "test"
 	label := &models.Label{
-		Name:      "test",
+		Name:      labelName,
 		Level:     common.LabelLevelUser,
 		Scope:     common.LabelScopeProject,
 		ProjectID: 1,
@@ -37,6 +38,24 @@ func TestMethodsOfLabel(t *testing.T) {
 	require.Nil(t, err)
 	label.ID = id
 
+	// add a label which has the same name to another project
+	projectID, err := AddProject(models.Project{
+		OwnerID: 1,
+		Name:    "project_for_label_test",
+	})
+	require.Nil(t, err)
+	defer GetOrmer().QueryTable(&models.Project{}).
+		Filter("project_id", projectID).Delete()
+
+	id2, err := AddLabel(&models.Label{
+		Name:      labelName,
+		Level:     common.LabelLevelUser,
+		Scope:     common.LabelScopeProject,
+		ProjectID: projectID,
+	})
+	require.Nil(t, err)
+	defer DeleteLabel(id2)
+
 	// get
 	l, err := GetLabel(id)
 	require.Nil(t, err)
diff --git a/tools/migration/db/db_meta.py b/tools/migration/db/db_meta.py
index 4fc2b5232..c012f9ff3 100644
--- a/tools/migration/db/db_meta.py
+++ b/tools/migration/db/db_meta.py
@@ -259,7 +259,7 @@ class HarborLabel(Base):
     creation_time = sa.Column(mysql.TIMESTAMP, server_default = sa.text("CURRENT_TIMESTAMP"))
     update_time = sa.Column(mysql.TIMESTAMP, server_default = sa.text("CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP"))
 
-    __table_args__ = (sa.UniqueConstraint('name', 'scope', name='unique_name_and_scope'),)
+    __table_args__ = (sa.UniqueConstraint('name', 'scope', 'project_id', name='unique_label'),)
 
 
 class HarborResourceLabel(Base):