diff --git a/action/protocol/staking/contractstaking/bucket.go b/action/protocol/staking/contractstaking/bucket.go
index ba7866d0da..f83edb4d4f 100644
--- a/action/protocol/staking/contractstaking/bucket.go
+++ b/action/protocol/staking/contractstaking/bucket.go
@@ -24,3 +24,22 @@ type Bucket struct {
 	AutoStake                 bool
 	ContractAddress           string // contract address for the bucket
 }
+
+func assembleBucket(token uint64, bi *bucketInfo, bt *BucketType, contractAddr string) (*Bucket, error) {
+	vb := Bucket{
+		Index:                     token,
+		StakedAmount:              bt.Amount,
+		StakedDurationBlockNumber: bt.Duration,
+		CreateBlockHeight:         bi.CreatedAt,
+		StakeStartBlockHeight:     bi.CreatedAt,
+		UnstakeStartBlockHeight:   bi.UnstakedAt,
+		AutoStake:                 bi.UnlockedAt == maxBlockNumber,
+		Candidate:                 bi.Delegate,
+		Owner:                     bi.Owner,
+		ContractAddress:           contractAddr,
+	}
+	if bi.UnlockedAt != maxBlockNumber {
+		vb.StakeStartBlockHeight = bi.UnlockedAt
+	}
+	return &vb, nil
+}
diff --git a/action/protocol/staking/contractstaking/cache.go b/action/protocol/staking/contractstaking/cache.go
new file mode 100644
index 0000000000..43ed459b56
--- /dev/null
+++ b/action/protocol/staking/contractstaking/cache.go
@@ -0,0 +1,188 @@
+// Copyright (c) 2023 IoTeX Foundation
+// This source code is provided 'as is' and no warranties are given as to title or non-infringement, merchantability
+// or fitness for purpose and, to the extent permitted by law, all liability for your use of the code is disclaimed.
+// This source code is governed by Apache License 2.0 that can be found in the LICENSE file.
+
+package contractstaking
+
+import (
+	"math/big"
+
+	"github.com/iotexproject/iotex-address/address"
+	"github.com/pkg/errors"
+)
+
+type (
+	contractStakingCache struct {
+		bucketInfoMap         map[uint64]*bucketInfo      // map[token]bucketInfo
+		candidateBucketMap    map[string]map[uint64]bool  // map[candidate]bucket
+		bucketTypeMap         map[uint64]*BucketType      // map[bucketTypeId]BucketType
+		propertyBucketTypeMap map[int64]map[uint64]uint64 // map[amount][duration]index
+		height                uint64
+		totalBucketCount      uint64 // total number of buckets including burned buckets
+		contractAddress       string // contract address for the bucket
+	}
+)
+
+var (
+	// ErrBucketNotExist is the error when bucket does not exist
+	ErrBucketNotExist = errors.New("bucket does not exist")
+)
+
+func newContractStakingCache(contractAddr string) *contractStakingCache {
+	cache := &contractStakingCache{
+		bucketInfoMap:         make(map[uint64]*bucketInfo),
+		bucketTypeMap:         make(map[uint64]*BucketType),
+		propertyBucketTypeMap: make(map[int64]map[uint64]uint64),
+		candidateBucketMap:    make(map[string]map[uint64]bool),
+		contractAddress:       contractAddr,
+	}
+	return cache
+}
+
+func (s *contractStakingCache) Height() uint64 {
+	return s.height
+}
+
+func (s *contractStakingCache) CandidateVotes(candidate address.Address) *big.Int {
+	votes := big.NewInt(0)
+	m, ok := s.candidateBucketMap[candidate.String()]
+	if !ok {
+		return votes
+	}
+	for id, existed := range m {
+		if !existed {
+			continue
+		}
+		bi := s.mustGetBucketInfo(id)
+		// only count the bucket that is not unstaked
+		if bi.UnstakedAt != maxBlockNumber {
+			continue
+		}
+		bt := s.mustGetBucketType(bi.TypeIndex)
+		votes.Add(votes, bt.Amount)
+	}
+	return votes
+}
+
+func (s *contractStakingCache) Buckets() ([]*Bucket, error) {
+	vbs := []*Bucket{}
+	for id, bi := range s.getAllBucketInfo() {
+		bt := s.mustGetBucketType(bi.TypeIndex)
+		vb, err := assembleBucket(id, bi, bt, s.contractAddress)
+		if err != nil {
+			return nil, err
+		}
+		vbs = append(vbs, vb)
+	}
+	return vbs, nil
+}
+
+func (s *contractStakingCache) Bucket(id uint64) (*Bucket, error) {
+	return s.getBucket(id)
+}
+
+func (s *contractStakingCache) BucketsByCandidate(candidate address.Address) ([]*Bucket, error) {
+	bucketMap := s.getBucketInfoByCandidate(candidate)
+	vbs := make([]*Bucket, 0, len(bucketMap))
+	for id := range bucketMap {
+		vb, err := s.getBucket(id)
+		if err != nil {
+			return nil, err
+		}
+		vbs = append(vbs, vb)
+	}
+	return vbs, nil
+}
+
+func (s *contractStakingCache) BucketsByIndices(indices []uint64) ([]*Bucket, error) {
+	vbs := make([]*Bucket, 0, len(indices))
+	for _, id := range indices {
+		vb, err := s.getBucket(id)
+		if err != nil {
+			return nil, err
+		}
+		vbs = append(vbs, vb)
+	}
+	return vbs, nil
+}
+
+func (s *contractStakingCache) TotalBucketCount() uint64 {
+	return s.totalBucketCount
+}
+
+func (s *contractStakingCache) ActiveBucketTypes() map[uint64]*BucketType {
+	m := make(map[uint64]*BucketType)
+	for k, v := range s.bucketTypeMap {
+		if v.ActivatedAt != maxBlockNumber {
+			m[k] = v
+		}
+	}
+	return m
+}
+
+func (s *contractStakingCache) getBucketTypeIndex(amount *big.Int, duration uint64) (uint64, bool) {
+	m, ok := s.propertyBucketTypeMap[amount.Int64()]
+	if !ok {
+		return 0, false
+	}
+	id, ok := m[duration]
+	return id, ok
+}
+
+func (s *contractStakingCache) getBucketType(id uint64) (*BucketType, bool) {
+	bt, ok := s.bucketTypeMap[id]
+	return bt, ok
+}
+
+func (s *contractStakingCache) mustGetBucketType(id uint64) *BucketType {
+	bt, ok := s.bucketTypeMap[id]
+	if !ok {
+		panic("bucket type not found")
+	}
+	return bt
+}
+
+func (s *contractStakingCache) getBucketInfo(id uint64) (*bucketInfo, bool) {
+	bi, ok := s.bucketInfoMap[id]
+	return bi, ok
+}
+
+func (s *contractStakingCache) mustGetBucketInfo(id uint64) *bucketInfo {
+	bt, ok := s.bucketInfoMap[id]
+	if !ok {
+		panic("bucket info not found")
+	}
+	return bt
+}
+
+func (s *contractStakingCache) getBucket(id uint64) (*Bucket, error) {
+	bi, ok := s.getBucketInfo(id)
+	if !ok {
+		return nil, errors.Wrapf(ErrBucketNotExist, "id %d", id)
+	}
+	bt := s.mustGetBucketType(bi.TypeIndex)
+	return assembleBucket(id, bi, bt, s.contractAddress)
+}
+
+func (s *contractStakingCache) getTotalBucketTypeCount() uint64 {
+	return uint64(len(s.bucketTypeMap))
+}
+
+func (s *contractStakingCache) getAllBucketInfo() map[uint64]*bucketInfo {
+	m := make(map[uint64]*bucketInfo)
+	for k, v := range s.bucketInfoMap {
+		m[k] = v
+	}
+	return m
+}
+
+func (s *contractStakingCache) getBucketInfoByCandidate(candidate address.Address) map[uint64]*bucketInfo {
+	m := make(map[uint64]*bucketInfo)
+	for k, v := range s.candidateBucketMap[candidate.String()] {
+		if v {
+			m[k] = s.bucketInfoMap[k]
+		}
+	}
+	return m
+}
diff --git a/action/protocol/staking/contractstaking/indexer.go b/action/protocol/staking/contractstaking/indexer.go
new file mode 100644
index 0000000000..876f99b178
--- /dev/null
+++ b/action/protocol/staking/contractstaking/indexer.go
@@ -0,0 +1,84 @@
+// Copyright (c) 2023 IoTeX Foundation
+// This source code is provided 'as is' and no warranties are given as to title or non-infringement, merchantability
+// or fitness for purpose and, to the extent permitted by law, all liability for your use of the code is disclaimed.
+// This source code is governed by Apache License 2.0 that can be found in the LICENSE file.
+
+package contractstaking
+
+import (
+	"math/big"
+
+	"github.com/ethereum/go-ethereum/common/math"
+	"github.com/iotexproject/iotex-address/address"
+
+	"github.com/iotexproject/iotex-core/db"
+)
+
+const (
+	maxBlockNumber uint64 = math.MaxUint64
+)
+
+type (
+	// Indexer is the contract staking indexer
+	// Main functions:
+	// 		1. handle contract staking contract events when new block comes to generate index data
+	// 		2. provide query interface for contract staking index data
+	Indexer struct {
+		kvstore         db.KVStore            // persistent storage, used to initialize index cache at startup
+		cache           *contractStakingCache // in-memory index for clean data, used to query index data
+		contractAddress string                // stake contract address
+	}
+)
+
+// NewContractStakingIndexer creates a new contract staking indexer
+func NewContractStakingIndexer(kvStore db.KVStore, contractAddr string) *Indexer {
+	return &Indexer{
+		kvstore: kvStore,
+		cache:   newContractStakingCache(contractAddr),
+	}
+}
+
+// Height returns the tip block height
+func (s *Indexer) Height() (uint64, error) {
+	return s.cache.Height(), nil
+}
+
+// CandidateVotes returns the candidate votes
+func (s *Indexer) CandidateVotes(candidate address.Address) *big.Int {
+	return s.cache.CandidateVotes(candidate)
+}
+
+// Buckets returns the buckets
+func (s *Indexer) Buckets() ([]*Bucket, error) {
+	return s.cache.Buckets()
+}
+
+// Bucket returns the bucket
+func (s *Indexer) Bucket(id uint64) (*Bucket, error) {
+	return s.cache.Bucket(id)
+}
+
+// BucketsByIndices returns the buckets by indices
+func (s *Indexer) BucketsByIndices(indices []uint64) ([]*Bucket, error) {
+	return s.cache.BucketsByIndices(indices)
+}
+
+// BucketsByCandidate returns the buckets by candidate
+func (s *Indexer) BucketsByCandidate(candidate address.Address) ([]*Bucket, error) {
+	return s.cache.BucketsByCandidate(candidate)
+}
+
+// TotalBucketCount returns the total bucket count including active and burnt buckets
+func (s *Indexer) TotalBucketCount() uint64 {
+	return s.cache.TotalBucketCount()
+}
+
+// BucketTypes returns the active bucket types
+func (s *Indexer) BucketTypes() ([]*BucketType, error) {
+	btMap := s.cache.ActiveBucketTypes()
+	bts := make([]*BucketType, 0, len(btMap))
+	for _, bt := range btMap {
+		bts = append(bts, bt)
+	}
+	return bts, nil
+}