diff --git a/pkg/mcs/utils/constant.go b/pkg/mcs/utils/constant.go
index 9c9eea777323..b73ddd7ed8fa 100644
--- a/pkg/mcs/utils/constant.go
+++ b/pkg/mcs/utils/constant.go
@@ -49,12 +49,16 @@ const (
 	// We also reserved 0 for the keyspace group for the same purpose.
 	DefaultKeyspaceGroupID = uint32(0)
 
+	// MicroserviceKey is the key of microservice.
+	MicroserviceKey = "ms"
 	// APIServiceName is the name of api server.
 	APIServiceName = "api"
 	// TSOServiceName is the name of tso server.
 	TSOServiceName = "tso"
 	// ResourceManagerServiceName is the name of resource manager server.
 	ResourceManagerServiceName = "resource_manager"
+	// KeyspaceGroupsKey is the path component of keyspace groups.
+	KeyspaceGroupsKey = "keyspace_groups"
 
 	// MaxKeyspaceGroupCount is the max count of keyspace groups. keyspace group in tso
 	// is the sharding unit, i.e., by the definition here, the max count of the shards
diff --git a/pkg/storage/endpoint/key_path.go b/pkg/storage/endpoint/key_path.go
index 9ae8a2850858..2eca0e6bf177 100644
--- a/pkg/storage/endpoint/key_path.go
+++ b/pkg/storage/endpoint/key_path.go
@@ -53,11 +53,10 @@ const (
 	resourceGroupStatesPath   = "states"
 	controllerConfigPath      = "controller"
 	// tso storage endpoint has prefix `tso`
-	microserviceKey = "ms"
-	tsoServiceKey   = utils.TSOServiceName
-	timestampKey    = "timestamp"
+	tsoServiceKey = utils.TSOServiceName
+	timestampKey  = "timestamp"
 
-	tsoKeyspaceGroupPrefix     = "tso/keyspace_groups"
+	tsoKeyspaceGroupPrefix     = tsoServiceKey + "/" + utils.KeyspaceGroupsKey
 	keyspaceGroupMembershipKey = "membership"
 
 	// we use uint64 to represent ID, the max length of uint64 is 20.
@@ -238,20 +237,10 @@ func KeyspaceGroupIDPath(id uint32) string {
 	return path.Join(tsoKeyspaceGroupPrefix, keyspaceGroupMembershipKey, encodeKeyspaceGroupID(id))
 }
 
-// ExtractKeyspaceGroupIDFromPath extracts keyspace group id from the given path, which contains
-// the pattern of `tso/keyspace_groups/membership/(\d{5})$`.
-func ExtractKeyspaceGroupIDFromPath(path string) (uint32, error) {
+// GetCompiledKeyspaceGroupIDRegexp returns the compiled regular expression for matching keyspace group id.
+func GetCompiledKeyspaceGroupIDRegexp() *regexp.Regexp {
 	pattern := strings.Join([]string{KeyspaceGroupIDPrefix(), `(\d{5})$`}, "/")
-	re := regexp.MustCompile(pattern)
-	match := re.FindStringSubmatch(path)
-	if match == nil {
-		return 0, fmt.Errorf("invalid keyspace group id path: %s", path)
-	}
-	id, err := strconv.ParseUint(match[1], 10, 32)
-	if err != nil {
-		return 0, fmt.Errorf("failed to parse keyspace group ID: %v", err)
-	}
-	return uint32(id), nil
+	return regexp.MustCompile(pattern)
 }
 
 // encodeKeyspaceGroupID from uint32 to string.
diff --git a/pkg/storage/endpoint/key_path_test.go b/pkg/storage/endpoint/key_path_test.go
index 270d1e266fe8..d6ef584105a4 100644
--- a/pkg/storage/endpoint/key_path_test.go
+++ b/pkg/storage/endpoint/key_path_test.go
@@ -27,51 +27,3 @@ func BenchmarkRegionPath(b *testing.B) {
 		_ = RegionPath(uint64(i))
 	}
 }
-
-func TestExtractKeyspaceGroupIDFromPath(t *testing.T) {
-	re := require.New(t)
-
-	rightCases := []struct {
-		path string
-		id   uint32
-	}{
-		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/00000", id: 0},
-		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/00001", id: 1},
-		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/12345", id: 12345},
-		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/99999", id: 99999},
-		{path: "tso/keyspace_groups/membership/00000", id: 0},
-		{path: "tso/keyspace_groups/membership/00001", id: 1},
-		{path: "tso/keyspace_groups/membership/12345", id: 12345},
-		{path: "tso/keyspace_groups/membership/99999", id: 99999},
-	}
-
-	for _, tt := range rightCases {
-		id, err := ExtractKeyspaceGroupIDFromPath(tt.path)
-		re.Equal(tt.id, id)
-		re.NoError(err)
-	}
-
-	wrongCases := []struct {
-		path string
-	}{
-		{path: ""},
-		{path: "00001"},
-		{path: "xxx/keyspace_groups/membership/00001"},
-		{path: "tso/xxxxxxxxxxxxxxx/membership/00001"},
-		{path: "tso/keyspace_groups/xxxxxxxxxx/00001"},
-		{path: "/pd/{cluster_id}/tso/keyspace_groups/xxxxxxxxxx/00001"},
-		{path: "/pd/{cluster_id}/xxx/keyspace_groups/membership/00001"},
-		{path: "/pd/{cluster_id}/tso/xxxxxxxxxxxxxxx/membership/00001"},
-		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/"},
-		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/0"},
-		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/0001"},
-		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/123456"},
-		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/1234a"},
-		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/12345a"},
-	}
-
-	for _, tt := range wrongCases {
-		_, err := ExtractKeyspaceGroupIDFromPath(tt.path)
-		re.Error(err)
-	}
-}
diff --git a/pkg/tso/keyspace_group_manager.go b/pkg/tso/keyspace_group_manager.go
index 6859ae82386f..37f80ad40ffd 100644
--- a/pkg/tso/keyspace_group_manager.go
+++ b/pkg/tso/keyspace_group_manager.go
@@ -20,6 +20,7 @@ import (
 	"fmt"
 	"net/http"
 	"path"
+	"regexp"
 	"sort"
 	"strings"
 	"sync"
@@ -46,9 +47,10 @@ import (
 )
 
 const (
-	// primaryElectionSuffix is the suffix of the key for keyspace group primary election
-	primaryElectionSuffix = "primary"
-	defaultRetryInterval  = 500 * time.Millisecond
+	keyspaceGroupsElectionPath = mcsutils.KeyspaceGroupsKey + "/election"
+	// leaderNameKey is the key for keyspace group primary election.
+	leaderNameKey        = "primary"
+	defaultRetryInterval = 500 * time.Millisecond
 )
 
 type state struct {
@@ -147,6 +149,32 @@ func (s *state) getKeyspaceGroupMetaWithCheck(
 		mcsutils.DefaultKeyspaceGroupID, nil
 }
 
+// kgPrimaryPathBuilder builds the path for keyspace group primary election.
+// The path for default keyspace group is "/ms/{cluster_id}/tso/00000/primary".
+// The path for non-default keyspace group is "/ms/{cluster_id}/tso/keyspace_groups/election/{group}/primary".
+type kgPrimaryPathBuilder struct {
+	// rootPath is "/ms/{cluster_id}/tso".
+	rootPath string
+	// defaultKeyspaceGroupIDPath is "/ms/{cluster_id}/tso/00000".
+	defaultKeyspaceGroupIDPath string
+}
+
+// getKeyspaceGroupIDPath returns the keyspace group primary ID path.
+// The path for default keyspace group is "/ms/{cluster_id}/tso/00000".
+// The path for non-default keyspace group is "/ms/{cluster_id}/tso/keyspace_groups/election/{group}".
+func (p *kgPrimaryPathBuilder) getKeyspaceGroupIDPath(keyspaceGroupID uint32) string {
+	if keyspaceGroupID == mcsutils.DefaultKeyspaceGroupID {
+		return p.defaultKeyspaceGroupIDPath
+	}
+	return path.Join(p.rootPath, keyspaceGroupsElectionPath, fmt.Sprintf("%05d", keyspaceGroupID))
+}
+
+// getCompiledNonDefaultIDRegexp returns the compiled regular expression for matching non-default keyspace group id.
+func (p *kgPrimaryPathBuilder) getCompiledNonDefaultIDRegexp() *regexp.Regexp {
+	pattern := strings.Join([]string{p.rootPath, keyspaceGroupsElectionPath, `(\d{5})`, leaderNameKey + `$`}, "/")
+	return regexp.MustCompile(pattern)
+}
+
 // KeyspaceGroupManager manages the members of the keyspace groups assigned to this host.
 // The replicas campaign for the leaders which provide the tso service for the corresponding
 // keyspace groups.
@@ -183,7 +211,7 @@ type KeyspaceGroupManager struct {
 	// tsoSvcRootPath defines the root path for all etcd paths used in the tso microservices.
 	// It is in the format of "/ms/<cluster-id>/tso".
 	// The main paths for different usages include:
-	// 1. The path for keyspace group primary election. Format: "/ms/{cluster_id}/tso/{group}/primary"
+	// 1. The path for keyspace group primary election. Format: "/ms/{cluster_id}/tso/election/{group}/primary"
 	// 2. The path for LoadTimestamp/SaveTimestamp in the storage endpoint for all the non-default
 	//    keyspace groups.
 	//    Key: /ms/{cluster_id}/tso/{group}/gta/timestamp
@@ -204,10 +232,14 @@ type KeyspaceGroupManager struct {
 	loadKeyspaceGroupsBatchSize int64
 	loadFromEtcdMaxRetryTimes   int
 
+	// compiledKGMembershipIDRegexp is the compiled regular expression for matching keyspace group id in the
+	// keyspace group membership path.
+	compiledKGMembershipIDRegexp *regexp.Regexp
 	// groupUpdateRetryList is the list of keyspace groups which failed to update and need to retry.
 	groupUpdateRetryList map[uint32]*endpoint.KeyspaceGroup
+	groupWatcher         *etcdutil.LoopWatcher
 
-	groupWatcher *etcdutil.LoopWatcher
+	primaryPathBuilder *kgPrimaryPathBuilder
 }
 
 // NewKeyspaceGroupManager creates a new Keyspace Group Manager.
@@ -244,6 +276,11 @@ func NewKeyspaceGroupManager(
 		kv.NewEtcdKVBase(kgm.etcdClient, kgm.legacySvcRootPath), nil)
 	kgm.tsoSvcStorage = endpoint.NewStorageEndpoint(
 		kv.NewEtcdKVBase(kgm.etcdClient, kgm.tsoSvcRootPath), nil)
+	kgm.compiledKGMembershipIDRegexp = endpoint.GetCompiledKeyspaceGroupIDRegexp()
+	kgm.primaryPathBuilder = &kgPrimaryPathBuilder{
+		rootPath:                   kgm.tsoSvcRootPath,
+		defaultKeyspaceGroupIDPath: path.Join(kgm.tsoSvcRootPath, "00000"),
+	}
 	kgm.state.initialize()
 	return kgm
 }
@@ -268,7 +305,7 @@ func (kgm *KeyspaceGroupManager) Initialize() error {
 		return nil
 	}
 	deleteFn := func(kv *mvccpb.KeyValue) error {
-		groupID, err := endpoint.ExtractKeyspaceGroupIDFromPath(string(kv.Key))
+		groupID, err := ExtractKeyspaceGroupIDFromPath(kgm.compiledKGMembershipIDRegexp, string(kv.Key))
 		if err != nil {
 			return err
 		}
@@ -303,6 +340,7 @@ func (kgm *KeyspaceGroupManager) Initialize() error {
 	if kgm.loadKeyspaceGroupsBatchSize > 0 {
 		kgm.groupWatcher.SetLoadBatchSize(kgm.loadKeyspaceGroupsBatchSize)
 	}
+
 	kgm.wg.Add(1)
 	go kgm.groupWatcher.StartWatchLoop()
 
@@ -388,8 +426,8 @@ func (kgm *KeyspaceGroupManager) updateKeyspaceGroup(group *endpoint.KeyspaceGro
 	// Initialize the participant info to join the primary election.
 	participant := member.NewParticipant(kgm.etcdClient)
 	participant.InitInfo(
-		uniqueName, uniqueID, path.Join(kgm.tsoSvcRootPath, fmt.Sprintf("%05d", group.ID)),
-		primaryElectionSuffix, "keyspace group primary election", kgm.cfg.GetAdvertiseListenAddr())
+		uniqueName, uniqueID, kgm.primaryPathBuilder.getKeyspaceGroupIDPath(group.ID),
+		leaderNameKey, "keyspace group primary election", kgm.cfg.GetAdvertiseListenAddr())
 	// If the keyspace group is in split, we should ensure that the primary elected by the new keyspace group
 	// is always on the same TSO Server node as the primary of the old keyspace group, and this constraint cannot
 	// be broken until the entire split process is completed.
diff --git a/pkg/tso/keyspace_group_manager_test.go b/pkg/tso/keyspace_group_manager_test.go
index 671fc8b73aa0..45e8803f14e7 100644
--- a/pkg/tso/keyspace_group_manager_test.go
+++ b/pkg/tso/keyspace_group_manager_test.go
@@ -183,7 +183,7 @@ func (suite *keyspaceGroupManagerTestSuite) TestLoadKeyspaceGroupsTimeout() {
 	re.NoError(failpoint.Enable("github.com/tikv/pd/pkg/utils/etcdutil/delayLoad", "return(3)"))
 	err := mgr.Initialize()
 	// If loading keyspace groups timeout, the initialization should fail with ErrLoadKeyspaceGroupsTerminated.
-	re.Equal(errs.ErrLoadKeyspaceGroupsTerminated, err)
+	re.True(strings.Contains(err.Error(), errs.ErrLoadKeyspaceGroupsTerminated.Error()))
 	re.NoError(failpoint.Disable("github.com/tikv/pd/pkg/utils/etcdutil/delayLoad"))
 }
 
@@ -592,9 +592,8 @@ func (suite *keyspaceGroupManagerTestSuite) newKeyspaceGroupManager(
 	electionNamePrefix, legacySvcRootPath, tsoSvcRootPath string,
 ) *KeyspaceGroupManager {
 	return NewKeyspaceGroupManager(
-		suite.ctx, tsoServiceID, suite.etcdClient, nil,
-		electionNamePrefix, legacySvcRootPath, tsoSvcRootPath,
-		suite.cfg)
+		suite.ctx, tsoServiceID, suite.etcdClient, nil, electionNamePrefix,
+		legacySvcRootPath, tsoSvcRootPath, suite.cfg)
 }
 
 // runTestLoadMultipleKeyspaceGroupsAssignment tests the loading of multiple keyspace group assignment.
diff --git a/pkg/tso/util.go b/pkg/tso/util.go
new file mode 100644
index 000000000000..d7672373a320
--- /dev/null
+++ b/pkg/tso/util.go
@@ -0,0 +1,35 @@
+// Copyright 2023 TiKV Project Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package tso
+
+import (
+	"fmt"
+	"regexp"
+	"strconv"
+)
+
+// ExtractKeyspaceGroupIDFromPath extracts keyspace group id from the given path, which contains
+// the pattern of `tso/keyspace_groups/membership/(\d{5})$`.
+func ExtractKeyspaceGroupIDFromPath(compiledRegexp *regexp.Regexp, path string) (uint32, error) {
+	match := compiledRegexp.FindStringSubmatch(path)
+	if match == nil {
+		return 0, fmt.Errorf("invalid keyspace group id path: %s", path)
+	}
+	id, err := strconv.ParseUint(match[1], 10, 32)
+	if err != nil {
+		return 0, fmt.Errorf("failed to parse keyspace group ID: %v", err)
+	}
+	return uint32(id), nil
+}
diff --git a/pkg/tso/util_test.go b/pkg/tso/util_test.go
new file mode 100644
index 000000000000..8b7c7a4ce0c0
--- /dev/null
+++ b/pkg/tso/util_test.go
@@ -0,0 +1,100 @@
+// Copyright 2023 TiKV Project Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package tso
+
+import (
+	"path"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"github.com/tikv/pd/pkg/storage/endpoint"
+)
+
+func TestExtractKeyspaceGroupIDFromKeyspaceGroupMembershipPath(t *testing.T) {
+	re := require.New(t)
+
+	compiledRegexp := endpoint.GetCompiledKeyspaceGroupIDRegexp()
+
+	rightCases := []struct {
+		path string
+		id   uint32
+	}{
+		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/00000", id: 0},
+		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/00001", id: 1},
+		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/12345", id: 12345},
+		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/99999", id: 99999},
+		{path: "tso/keyspace_groups/membership/00000", id: 0},
+		{path: "tso/keyspace_groups/membership/00001", id: 1},
+		{path: "tso/keyspace_groups/membership/12345", id: 12345},
+		{path: "tso/keyspace_groups/membership/99999", id: 99999},
+	}
+
+	for _, tt := range rightCases {
+		id, err := ExtractKeyspaceGroupIDFromPath(compiledRegexp, tt.path)
+		re.Equal(tt.id, id)
+		re.NoError(err)
+	}
+
+	wrongCases := []struct {
+		path string
+	}{
+		{path: ""},
+		{path: "00001"},
+		{path: "xxx/keyspace_groups/membership/00001"},
+		{path: "tso/xxxxxxxxxxxxxxx/membership/00001"},
+		{path: "tso/keyspace_groups/xxxxxxxxxx/00001"},
+		{path: "/pd/{cluster_id}/tso/keyspace_groups/xxxxxxxxxx/00001"},
+		{path: "/pd/{cluster_id}/xxx/keyspace_groups/membership/00001"},
+		{path: "/pd/{cluster_id}/tso/xxxxxxxxxxxxxxx/membership/00001"},
+		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/"},
+		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/0"},
+		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/0001"},
+		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/123456"},
+		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/1234a"},
+		{path: "/pd/{cluster_id}/tso/keyspace_groups/membership/12345a"},
+	}
+
+	for _, tt := range wrongCases {
+		_, err := ExtractKeyspaceGroupIDFromPath(compiledRegexp, tt.path)
+		re.Error(err)
+	}
+}
+
+func TestExtractKeyspaceGroupIDFromKeyspaceGroupPrimaryPath(t *testing.T) {
+	re := require.New(t)
+
+	tsoSvcRootPath := "/ms/111/tso"
+	primaryPathBuilder := &kgPrimaryPathBuilder{
+		rootPath:                   tsoSvcRootPath,
+		defaultKeyspaceGroupIDPath: path.Join(tsoSvcRootPath, "00000"),
+	}
+
+	compiledRegexp := primaryPathBuilder.getCompiledNonDefaultIDRegexp()
+
+	rightCases := []struct {
+		path string
+		id   uint32
+	}{
+		{path: "/ms/111/tso/keyspace_groups/election/00001/primary", id: 1},
+		{path: "/ms/111/tso/keyspace_groups/election/12345/primary", id: 12345},
+		{path: "/ms/111/tso/keyspace_groups/election/99999/primary", id: 99999},
+	}
+
+	for _, tt := range rightCases {
+		id, err := ExtractKeyspaceGroupIDFromPath(compiledRegexp, tt.path)
+		re.Equal(tt.id, id)
+		re.NoError(err)
+	}
+}