diff --git a/core/chain_makers.go b/core/chain_makers.go
index 6ecf0014b..6da870aa2 100644
--- a/core/chain_makers.go
+++ b/core/chain_makers.go
@@ -71,6 +71,11 @@ func (b *BlockGen) SetNonce(nonce types.BlockNonce) {
 	b.header.Nonce = nonce
 }
 
+// SetShardId sets the shardId field of the generated block.
+func (b *BlockGen) SetShardId(shardId types.ShardId) {
+	b.header.ShardId = shardId
+}
+
 // AddTx adds a transaction to the generated block. If no coinbase has
 // been set, the block's coinbase is set to the zero address.
 //
diff --git a/core/genesis.go b/core/genesis.go
index f73900b8d..4828a4805 100644
--- a/core/genesis.go
+++ b/core/genesis.go
@@ -45,6 +45,7 @@ var errGenesisNoConfig = errors.New("genesis has no chain configuration")
 type Genesis struct {
 	Config     *params.ChainConfig `json:"config"`
 	Nonce      uint64              `json:"nonce"`
+	ShardId    uint16              `json:"shardId"`
 	Timestamp  uint64              `json:"timestamp"`
 	ExtraData  []byte              `json:"extraData"`
 	GasLimit   uint64              `json:"gasLimit"   gencodec:"required"`
@@ -234,6 +235,7 @@ func (g *Genesis) ToBlock(db hdb.Database) *types.Block {
 	head := &types.Header{
 		Number:     new(big.Int).SetUint64(g.Number),
 		Nonce:      types.EncodeNonce(g.Nonce),
+		ShardId:    types.EncodeShardId(g.ShardId),
 		Time:       new(big.Int).SetUint64(g.Timestamp),
 		ParentHash: g.ParentHash,
 		Extra:      g.ExtraData,
diff --git a/core/types/block.go b/core/types/block.go
index 28454d09b..bb6d161df 100644
--- a/core/types/block.go
+++ b/core/types/block.go
@@ -52,6 +52,13 @@ func EncodeNonce(i uint64) BlockNonce {
 	return n
 }
 
+// EncodeShardId converts the given integer to a shard id.
+func EncodeShardId(i uint16) ShardId {
+	var n ShardId
+	binary.BigEndian.PutUint16(n[:], i)
+	return n
+}
+
 // Uint64 returns the integer value of a block nonce.
 func (n BlockNonce) Uint64() uint64 {
 	return binary.BigEndian.Uint64(n[:])
diff --git a/harmony/main.go b/harmony/main.go
index 99ca260d5..be0df947d 100644
--- a/harmony/main.go
+++ b/harmony/main.go
@@ -51,8 +51,9 @@ func main() {
 	var (
 		database = db.NewMemDatabase()
 		gspec    = core.Genesis{
-			Config: chainConfig,
-			Alloc:  core.GenesisAlloc{testBankAddress: {Balance: testBankFunds}},
+			Config:  chainConfig,
+			Alloc:   core.GenesisAlloc{testBankAddress: {Balance: testBankFunds}},
+			ShardId: 10,
 		}
 	)
 
@@ -74,6 +75,7 @@ func main() {
 	if n > 0 {
 		blocks, _ := core.GenerateChain(chainConfig, genesis, consensus.NewFaker(), database, n, func(i int, gen *core.BlockGen) {
 			gen.SetCoinbase(testBankAddress)
+			gen.SetShardId(types.EncodeShardId(10))
 			gen.AddTx(pendingTxs[i])
 		})
 		if _, err := chain.InsertChain(blocks); err != nil {
@@ -83,16 +85,13 @@ func main() {
 
 	txs := make([]*types.Transaction, 100)
 	worker := worker.New(params.TestChainConfig, chain, consensus.NewFaker())
-	fmt.Println(worker.GetCurrentState().GetBalance(testBankAddress))
-
+	nonce := worker.GetCurrentState().GetNonce(crypto.PubkeyToAddress(testBankKey.PublicKey))
 	for i, _ := range txs {
 		randomUserKey, _ := crypto.GenerateKey()
 		randomUserAddress := crypto.PubkeyToAddress(randomUserKey.PublicKey)
-		tx, _ := types.SignTx(types.NewTransaction(worker.GetCurrentState().GetNonce(crypto.PubkeyToAddress(testBankKey.PublicKey)), randomUserAddress, big.NewInt(1000), params.TxGas, nil, nil), types.HomesteadSigner{}, testBankKey)
+		tx, _ := types.SignTx(types.NewTransaction(nonce+uint64(i), randomUserAddress, big.NewInt(1000), params.TxGas, nil, nil), types.HomesteadSigner{}, testBankKey)
 		txs[i] = tx
 	}
 
 	worker.CommitTransactions(txs, crypto.PubkeyToAddress(testBankKey.PublicKey))
-
-	fmt.Println(worker.GetCurrentState().GetBalance(testBankAddress))
 }