diff --git a/pkg/consensus/consensus.go b/pkg/consensus/consensus.go
index 921da8659..d41373af4 100644
--- a/pkg/consensus/consensus.go
+++ b/pkg/consensus/consensus.go
@@ -341,7 +341,19 @@ func (s *service) getTx(h util.Uint256) block.Transaction {
 
 func (s *service) verifyBlock(b block.Block) bool {
 	coreb := &b.(*neoBlock).Block
+
+	maxBlockSize := int(s.Chain.GetMaxBlockSize())
+	size := io.GetVarSize(coreb)
+	if size > maxBlockSize {
+		s.log.Warn("proposed block size exceeds policy max block size",
+			zap.Int("max size allowed", maxBlockSize),
+			zap.Int("block size", size))
+		return false
+	}
+
+	var fee int64
 	for _, tx := range coreb.Transactions {
+		fee += tx.SystemFee
 		if err := s.Chain.VerifyTx(tx, coreb); err != nil {
 			s.log.Warn("invalid transaction in proposed block",
 				zap.Stringer("hash", tx.Hash()),
@@ -350,6 +362,14 @@ func (s *service) verifyBlock(b block.Block) bool {
 		}
 	}
 
+	maxBlockSysFee := s.Chain.GetMaxBlockSystemFee()
+	if fee > maxBlockSysFee {
+		s.log.Warn("proposed block system fee exceeds policy max block system fee",
+			zap.Int("max system fee allowed", int(maxBlockSysFee)),
+			zap.Int("block system fee", int(fee)))
+		return false
+	}
+
 	return true
 }
 
diff --git a/pkg/core/blockchain.go b/pkg/core/blockchain.go
index cd85cb01d..bd479dba1 100644
--- a/pkg/core/blockchain.go
+++ b/pkg/core/blockchain.go
@@ -1147,6 +1147,16 @@ func (bc *Blockchain) FeePerByte() int64 {
 	return bc.contracts.Policy.GetFeePerByteInternal(bc.dao)
 }
 
+// GetMaxBlockSize returns maximum allowed block size from native Policy contract.
+func (bc *Blockchain) GetMaxBlockSize() uint32 {
+	return bc.contracts.Policy.GetMaxBlockSizeInternal(bc.dao)
+}
+
+// GetMaxBlockSystemFee returns maximum block system fee from native Policy contract.
+func (bc *Blockchain) GetMaxBlockSystemFee() int64 {
+	return bc.contracts.Policy.GetMaxBlockSystemFeeInternal(bc.dao)
+}
+
 // GetMemPool returns the memory pool of the blockchain.
 func (bc *Blockchain) GetMemPool() *mempool.Pool {
 	return &bc.memPool
@@ -1159,6 +1169,21 @@ func (bc *Blockchain) ApplyPolicyToTxSet(txes []*transaction.Transaction) []*tra
 	if maxTx != 0 && len(txes) > int(maxTx) {
 		txes = txes[:maxTx]
 	}
+	maxBlockSize := bc.contracts.Policy.GetMaxBlockSizeInternal(bc.dao)
+	maxBlockSysFee := bc.contracts.Policy.GetMaxBlockSystemFeeInternal(bc.dao)
+	var (
+		blockSize uint32
+		sysFee    int64
+	)
+	blockSize = uint32(io.GetVarSize(new(block.Block)) + io.GetVarSize(len(txes)+1))
+	for i, tx := range txes {
+		blockSize += uint32(io.GetVarSize(tx))
+		sysFee += tx.SystemFee
+		if blockSize > maxBlockSize || sysFee > maxBlockSysFee {
+			txes = txes[:i]
+			break
+		}
+	}
 	return txes
 }
 
@@ -1194,9 +1219,13 @@ func (bc *Blockchain) verifyTx(t *transaction.Transaction, block *block.Block) e
 			return !blockedAccounts[i].Less(h)
 		})
 		if i != len(blockedAccounts) && blockedAccounts[i].Equals(h) {
-			return errors.Errorf("policy check failed")
+			return errors.Errorf("policy check failed: account %s is blocked", h.StringLE())
 		}
 	}
+	maxBlockSystemFee := bc.contracts.Policy.GetMaxBlockSystemFeeInternal(bc.dao)
+	if maxBlockSystemFee < t.SystemFee {
+		return errors.Errorf("policy check failed: transaction's fee shouldn't exceed maximum block system fee %d", maxBlockSystemFee)
+	}
 	balance := bc.GetUtilityTokenBalance(t.Sender)
 	need := t.SystemFee + t.NetworkFee
 	if balance.Cmp(big.NewInt(need)) < 0 {
diff --git a/pkg/core/blockchainer/blockchainer.go b/pkg/core/blockchainer/blockchainer.go
index fc9ca0110..b1ff94f12 100644
--- a/pkg/core/blockchainer/blockchainer.go
+++ b/pkg/core/blockchainer/blockchainer.go
@@ -50,6 +50,8 @@ type Blockchainer interface {
 	GetTestVM(tx *transaction.Transaction) *vm.VM
 	GetTransaction(util.Uint256) (*transaction.Transaction, uint32, error)
 	mempool.Feer // fee interface
+	GetMaxBlockSize() uint32
+	GetMaxBlockSystemFee() int64
 	PoolTx(*transaction.Transaction) error
 	SubscribeForBlocks(ch chan<- *block.Block)
 	SubscribeForExecutions(ch chan<- *state.AppExecResult)
diff --git a/pkg/core/native/policy.go b/pkg/core/native/policy.go
index 04ff6a72a..9d7c31cad 100644
--- a/pkg/core/native/policy.go
+++ b/pkg/core/native/policy.go
@@ -26,6 +26,9 @@ const (
 	defaultMaxTransactionsPerBlock = 512
 	defaultFeePerByte              = 1000
 	defaultMaxVerificationGas      = 50000000
+	defaultMaxBlockSystemFee       = 9000 * GASFactor
+	// minBlockSystemFee is the minimum allowed system fee per block.
+	minBlockSystemFee = 4007600
 )
 
 var (
@@ -38,7 +41,9 @@ var (
 	// blockedAccountsKey is a key used to store the list of blocked accounts.
 	blockedAccountsKey = []byte{15}
 	// maxBlockSizeKey is a key used to store the maximum block size value.
-	maxBlockSizeKey = []byte{16}
+	maxBlockSizeKey = []byte{12}
+	// maxBlockSystemFeeKey is a key used to store the maximum block system fee value.
+	maxBlockSystemFeeKey = []byte{17}
 )
 
 // Policy represents Policy native contract.
@@ -52,6 +57,7 @@ type Policy struct {
 	maxTransactionsPerBlock uint32
 	maxBlockSize            uint32
 	feePerByte              int64
+	maxBlockSystemFee       int64
 	maxVerificationGas      int64
 }
 
@@ -65,44 +71,53 @@ func newPolicy() *Policy {
 	p.Manifest.Features |= smartcontract.HasStorage
 
 	desc := newDescriptor("getMaxTransactionsPerBlock", smartcontract.IntegerType)
-	md := newMethodAndPrice(p.getMaxTransactionsPerBlock, 1000000, smartcontract.NoneFlag)
+	md := newMethodAndPrice(p.getMaxTransactionsPerBlock, 1000000, smartcontract.AllowStates)
 	p.AddMethod(md, desc, true)
 
 	desc = newDescriptor("getMaxBlockSize", smartcontract.IntegerType)
-	md = newMethodAndPrice(p.getMaxBlockSize, 1000000, smartcontract.NoneFlag)
+	md = newMethodAndPrice(p.getMaxBlockSize, 1000000, smartcontract.AllowStates)
 	p.AddMethod(md, desc, true)
 
 	desc = newDescriptor("getFeePerByte", smartcontract.IntegerType)
-	md = newMethodAndPrice(p.getFeePerByte, 1000000, smartcontract.NoneFlag)
+	md = newMethodAndPrice(p.getFeePerByte, 1000000, smartcontract.AllowStates)
 	p.AddMethod(md, desc, true)
 
 	desc = newDescriptor("getBlockedAccounts", smartcontract.ArrayType)
-	md = newMethodAndPrice(p.getBlockedAccounts, 1000000, smartcontract.NoneFlag)
+	md = newMethodAndPrice(p.getBlockedAccounts, 1000000, smartcontract.AllowStates)
+	p.AddMethod(md, desc, true)
+
+	desc = newDescriptor("getMaxBlockSystemFee", smartcontract.IntegerType)
+	md = newMethodAndPrice(p.getMaxBlockSystemFee, 1000000, smartcontract.AllowStates)
 	p.AddMethod(md, desc, true)
 
 	desc = newDescriptor("setMaxBlockSize", smartcontract.BoolType,
 		manifest.NewParameter("value", smartcontract.IntegerType))
-	md = newMethodAndPrice(p.setMaxBlockSize, 3000000, smartcontract.NoneFlag)
+	md = newMethodAndPrice(p.setMaxBlockSize, 3000000, smartcontract.AllowModifyStates)
 	p.AddMethod(md, desc, false)
 
 	desc = newDescriptor("setMaxTransactionsPerBlock", smartcontract.BoolType,
 		manifest.NewParameter("value", smartcontract.IntegerType))
-	md = newMethodAndPrice(p.setMaxTransactionsPerBlock, 3000000, smartcontract.NoneFlag)
+	md = newMethodAndPrice(p.setMaxTransactionsPerBlock, 3000000, smartcontract.AllowModifyStates)
 	p.AddMethod(md, desc, false)
 
 	desc = newDescriptor("setFeePerByte", smartcontract.BoolType,
 		manifest.NewParameter("value", smartcontract.IntegerType))
-	md = newMethodAndPrice(p.setFeePerByte, 3000000, smartcontract.NoneFlag)
+	md = newMethodAndPrice(p.setFeePerByte, 3000000, smartcontract.AllowModifyStates)
+	p.AddMethod(md, desc, false)
+
+	desc = newDescriptor("setMaxBlockSystemFee", smartcontract.BoolType,
+		manifest.NewParameter("value", smartcontract.IntegerType))
+	md = newMethodAndPrice(p.setMaxBlockSystemFee, 3000000, smartcontract.AllowModifyStates)
 	p.AddMethod(md, desc, false)
 
 	desc = newDescriptor("blockAccount", smartcontract.BoolType,
 		manifest.NewParameter("account", smartcontract.Hash160Type))
-	md = newMethodAndPrice(p.blockAccount, 3000000, smartcontract.NoneFlag)
+	md = newMethodAndPrice(p.blockAccount, 3000000, smartcontract.AllowModifyStates)
 	p.AddMethod(md, desc, false)
 
 	desc = newDescriptor("unblockAccount", smartcontract.BoolType,
 		manifest.NewParameter("account", smartcontract.Hash160Type))
-	md = newMethodAndPrice(p.unblockAccount, 3000000, smartcontract.NoneFlag)
+	md = newMethodAndPrice(p.unblockAccount, 3000000, smartcontract.AllowModifyStates)
 	p.AddMethod(md, desc, false)
 
 	desc = newDescriptor("onPersist", smartcontract.VoidType)
@@ -140,6 +155,12 @@ func (p *Policy) Initialize(ic *interop.Context) error {
 		return err
 	}
 
+	binary.LittleEndian.PutUint64(si.Value, defaultMaxBlockSystemFee)
+	err = ic.DAO.PutStorageItem(p.ContractID, maxBlockSystemFeeKey, si)
+	if err != nil {
+		return err
+	}
+
 	ba := new(BlockedAccounts)
 	si.Value = ba.Bytes()
 	err = ic.DAO.PutStorageItem(p.ContractID, blockedAccountsKey, si)
@@ -151,6 +172,7 @@ func (p *Policy) Initialize(ic *interop.Context) error {
 	p.maxTransactionsPerBlock = defaultMaxTransactionsPerBlock
 	p.maxBlockSize = defaultMaxBlockSize
 	p.feePerByte = defaultFeePerByte
+	p.maxBlockSystemFee = defaultMaxBlockSystemFee
 	p.maxVerificationGas = defaultMaxVerificationGas
 
 	return nil
@@ -178,6 +200,9 @@ func (p *Policy) OnPersistEnd(dao dao.DAO) {
 	feePerByte := p.getInt64WithKey(dao, feePerByteKey)
 	p.feePerByte = feePerByte
 
+	maxBlockSystemFee := p.getInt64WithKey(dao, maxBlockSystemFeeKey)
+	p.maxBlockSystemFee = maxBlockSystemFee
+
 	p.isValid = true
 }
 
@@ -200,12 +225,17 @@ func (p *Policy) GetMaxTransactionsPerBlockInternal(dao dao.DAO) uint32 {
 
 // getMaxBlockSize is Policy contract method and returns maximum block size.
 func (p *Policy) getMaxBlockSize(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
+	return stackitem.NewBigInteger(big.NewInt(int64(p.GetMaxBlockSizeInternal(ic.DAO))))
+}
+
+// GetMaxBlockSizeInternal returns maximum block size.
+func (p *Policy) GetMaxBlockSizeInternal(dao dao.DAO) uint32 {
 	p.lock.RLock()
 	defer p.lock.RUnlock()
 	if p.isValid {
-		return stackitem.NewBigInteger(big.NewInt(int64(p.maxBlockSize)))
+		return p.maxBlockSize
 	}
-	return stackitem.NewBigInteger(big.NewInt(int64(p.getUint32WithKey(ic.DAO, maxBlockSizeKey))))
+	return p.getUint32WithKey(dao, maxBlockSizeKey)
 }
 
 // getFeePerByte is Policy contract method and returns required transaction's fee
@@ -229,6 +259,22 @@ func (p *Policy) GetMaxVerificationGas(_ dao.DAO) int64 {
 	return p.maxVerificationGas
 }
 
+// getMaxBlockSystemFee is Policy contract method and returns the maximum overall
+// system fee per block.
+func (p *Policy) getMaxBlockSystemFee(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
+	return stackitem.NewBigInteger(big.NewInt(p.GetMaxBlockSystemFeeInternal(ic.DAO)))
+}
+
+// GetMaxBlockSystemFeeInternal the maximum overall system fee per block.
+func (p *Policy) GetMaxBlockSystemFeeInternal(dao dao.DAO) int64 {
+	p.lock.RLock()
+	defer p.lock.RUnlock()
+	if p.isValid {
+		return p.maxBlockSystemFee
+	}
+	return p.getInt64WithKey(dao, maxBlockSystemFeeKey)
+}
+
 // getBlockedAccounts is Policy contract method and returns list of blocked
 // accounts hashes.
 func (p *Policy) getBlockedAccounts(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
@@ -316,6 +362,29 @@ func (p *Policy) setFeePerByte(ic *interop.Context, args []stackitem.Item) stack
 	return stackitem.NewBool(true)
 }
 
+// setMaxBlockSystemFee is Policy contract method and sets the maximum system fee per block.
+func (p *Policy) setMaxBlockSystemFee(ic *interop.Context, args []stackitem.Item) stackitem.Item {
+	ok, err := p.checkValidators(ic)
+	if err != nil {
+		panic(err)
+	}
+	if !ok {
+		return stackitem.NewBool(false)
+	}
+	value := toBigInt(args[0]).Int64()
+	if value <= minBlockSystemFee {
+		return stackitem.NewBool(false)
+	}
+	p.lock.Lock()
+	defer p.lock.Unlock()
+	err = p.setInt64WithKey(ic.DAO, maxBlockSystemFeeKey, value)
+	if err != nil {
+		panic(err)
+	}
+	p.isValid = false
+	return stackitem.NewBool(true)
+}
+
 // blockAccount is Policy contract method and adds given account hash to the list
 // of blocked accounts.
 func (p *Policy) blockAccount(ic *interop.Context, args []stackitem.Item) stackitem.Item {
diff --git a/pkg/core/native_policy_test.go b/pkg/core/native_policy_test.go
index 88b246335..e38b789d3 100644
--- a/pkg/core/native_policy_test.go
+++ b/pkg/core/native_policy_test.go
@@ -47,7 +47,12 @@ func TestMaxBlockSize(t *testing.T) {
 	chain := newTestChain(t)
 	defer chain.Close()
 
-	t.Run("get", func(t *testing.T) {
+	t.Run("get, internal method", func(t *testing.T) {
+		n := chain.contracts.Policy.GetMaxBlockSizeInternal(chain.dao)
+		require.Equal(t, 1024*256, int(n))
+	})
+
+	t.Run("get, contract method", func(t *testing.T) {
 		res, err := invokeNativePolicyMethod(chain, "getMaxBlockSize")
 		require.NoError(t, err)
 		checkResult(t, res, stackitem.NewBigInteger(big.NewInt(1024*256)))
@@ -92,6 +97,52 @@ func TestFeePerByte(t *testing.T) {
 	})
 }
 
+func TestBlockSystemFee(t *testing.T) {
+	chain := newTestChain(t)
+	defer chain.Close()
+
+	t.Run("get, internal method", func(t *testing.T) {
+		n := chain.contracts.Policy.GetMaxBlockSystemFeeInternal(chain.dao)
+		require.Equal(t, 9000*native.GASFactor, int(n))
+	})
+
+	t.Run("get", func(t *testing.T) {
+		res, err := invokeNativePolicyMethod(chain, "getMaxBlockSystemFee")
+		require.NoError(t, err)
+		checkResult(t, res, smartcontract.Parameter{
+			Type:  smartcontract.IntegerType,
+			Value: 9000 * native.GASFactor,
+		})
+		require.NoError(t, chain.persist())
+	})
+
+	t.Run("set, too low fee", func(t *testing.T) {
+		res, err := invokeNativePolicyMethod(chain, "setMaxBlockSystemFee", bigint.ToBytes(big.NewInt(4007600)))
+		require.NoError(t, err)
+		checkResult(t, res, smartcontract.Parameter{
+			Type:  smartcontract.BoolType,
+			Value: false,
+		})
+	})
+
+	t.Run("set, success", func(t *testing.T) {
+		res, err := invokeNativePolicyMethod(chain, "setMaxBlockSystemFee", bigint.ToBytes(big.NewInt(100000000)))
+		require.NoError(t, err)
+		checkResult(t, res, smartcontract.Parameter{
+			Type:  smartcontract.BoolType,
+			Value: true,
+		})
+		require.NoError(t, chain.persist())
+		res, err = invokeNativePolicyMethod(chain, "getMaxBlockSystemFee")
+		require.NoError(t, err)
+		checkResult(t, res, smartcontract.Parameter{
+			Type:  smartcontract.IntegerType,
+			Value: 100000000,
+		})
+		require.NoError(t, chain.persist())
+	})
+}
+
 func TestBlockedAccounts(t *testing.T) {
 	chain := newTestChain(t)
 	defer chain.Close()
diff --git a/pkg/network/helper_test.go b/pkg/network/helper_test.go
index 2e7d336e6..45ccc3615 100644
--- a/pkg/network/helper_test.go
+++ b/pkg/network/helper_test.go
@@ -40,6 +40,14 @@ func (chain testChain) FeePerByte() int64 {
 	panic("TODO")
 }
 
+func (chain testChain) GetMaxBlockSystemFee() int64 {
+	panic("TODO")
+}
+
+func (chain testChain) GetMaxBlockSize() uint32 {
+	panic("TODO")
+}
+
 func (chain testChain) AddHeaders(...*block.Header) error {
 	panic("TODO")
 }