diff --git a/pkg/compiler/syscall_test.go b/pkg/compiler/syscall_test.go
index e9598ae9f..cfb2f6bf6 100644
--- a/pkg/compiler/syscall_test.go
+++ b/pkg/compiler/syscall_test.go
@@ -90,7 +90,6 @@ func TestSyscallExecution(t *testing.T) {
 		"storage.Put":                        {interopnames.SystemStoragePut, []string{sctx, b, b}, true},
 		"storage.ConvertContextToReadOnly":   {interopnames.SystemStorageAsReadOnly, []string{sctx}, false},
 		"crypto.ECDSASecp256r1CheckMultisig": {interopnames.NeoCryptoCheckMultisigWithECDsaSecp256r1, []string{b, pubs, sigs}, false},
-		"crypto.ECDSASecp256k1CheckMultisig": {interopnames.NeoCryptoCheckMultisigWithECDsaSecp256k1, []string{b, pubs, sigs}, false},
 		"crypto.CheckSig":                    {interopnames.NeoCryptoCheckSig, []string{pub, sig}, false},
 	}
 	ic := &interop.Context{}
diff --git a/pkg/core/interop/crypto/ecdsa.go b/pkg/core/interop/crypto/ecdsa.go
index a6dea4311..91004f902 100644
--- a/pkg/core/interop/crypto/ecdsa.go
+++ b/pkg/core/interop/crypto/ecdsa.go
@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 
-	"github.com/btcsuite/btcd/btcec"
 	"github.com/nspcc-dev/neo-go/pkg/core/fee"
 	"github.com/nspcc-dev/neo-go/pkg/core/interop"
 	"github.com/nspcc-dev/neo-go/pkg/crypto"
@@ -19,18 +18,6 @@ import (
 // ECDSASecp256r1CheckMultisig checks multiple ECDSA signatures at once using
 // Secp256r1 elliptic curve.
 func ECDSASecp256r1CheckMultisig(ic *interop.Context) error {
-	return ecdsaCheckMultisig(ic, elliptic.P256())
-}
-
-// ECDSASecp256k1CheckMultisig checks multiple ECDSA signatures at once using
-// Secp256k1 elliptic curve.
-func ECDSASecp256k1CheckMultisig(ic *interop.Context) error {
-	return ecdsaCheckMultisig(ic, btcec.S256())
-}
-
-// ecdsaCheckMultisig is internal representation of ECDSASecp256r1CheckMultisig and
-// ECDSASecp256k1CheckMultisig
-func ecdsaCheckMultisig(ic *interop.Context, curve elliptic.Curve) error {
 	hashToCheck, err := getMessageHash(ic, ic.VM.Estack().Pop().Item())
 	if err != nil {
 		return err
@@ -51,7 +38,7 @@ func ecdsaCheckMultisig(ic *interop.Context, curve elliptic.Curve) error {
 	if len(pkeys) < len(sigs) {
 		return errors.New("more signatures than there are keys")
 	}
-	sigok := vm.CheckMultisigPar(ic.VM, curve, hashToCheck.BytesBE(), pkeys, sigs)
+	sigok := vm.CheckMultisigPar(ic.VM, elliptic.P256(), hashToCheck.BytesBE(), pkeys, sigs)
 	ic.VM.Estack().PushVal(sigok)
 	return nil
 }
diff --git a/pkg/core/interop/crypto/ecdsa_test.go b/pkg/core/interop/crypto/ecdsa_test.go
index 097cf593e..73140dd4b 100644
--- a/pkg/core/interop/crypto/ecdsa_test.go
+++ b/pkg/core/interop/crypto/ecdsa_test.go
@@ -20,18 +20,14 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-func initCHECKMULTISIG(isR1 bool, msg []byte, n int) ([]stackitem.Item, []stackitem.Item, map[string]*keys.PublicKey, error) {
+func initCHECKMULTISIG(msg []byte, n int) ([]stackitem.Item, []stackitem.Item, map[string]*keys.PublicKey, error) {
 	var err error
 
 	keyMap := make(map[string]*keys.PublicKey)
 	pkeys := make([]*keys.PrivateKey, n)
 	pubs := make([]stackitem.Item, n)
 	for i := range pubs {
-		if isR1 {
-			pkeys[i], err = keys.NewPrivateKey()
-		} else {
-			pkeys[i], err = keys.NewSecp256k1PrivateKey()
-		}
+		pkeys[i], err = keys.NewPrivateKey()
 		if err != nil {
 			return nil, nil, nil, err
 		}
@@ -64,14 +60,10 @@ func subSlice(arr []stackitem.Item, indices []int) []stackitem.Item {
 	return result
 }
 
-func initCheckMultisigVMNoArgs(isR1 bool) *vm.VM {
+func initCheckMultisigVMNoArgs() *vm.VM {
 	buf := make([]byte, 5)
 	buf[0] = byte(opcode.SYSCALL)
-	if isR1 {
-		binary.LittleEndian.PutUint32(buf[1:], ecdsaSecp256r1CheckMultisigID)
-	} else {
-		binary.LittleEndian.PutUint32(buf[1:], ecdsaSecp256k1CheckMultisigID)
-	}
+	binary.LittleEndian.PutUint32(buf[1:], ecdsaSecp256r1CheckMultisigID)
 
 	ic := &interop.Context{Trigger: trigger.Verification}
 	Register(ic)
@@ -80,11 +72,11 @@ func initCheckMultisigVMNoArgs(isR1 bool) *vm.VM {
 	return v
 }
 
-func initCHECKMULTISIGVM(t *testing.T, isR1 bool, n int, ik, is []int) *vm.VM {
-	v := initCheckMultisigVMNoArgs(isR1)
+func initCHECKMULTISIGVM(t *testing.T, n int, ik, is []int) *vm.VM {
+	v := initCheckMultisigVMNoArgs()
 	msg := []byte("NEO - An Open Network For Smart Economy")
 
-	pubs, sigs, _, err := initCHECKMULTISIG(isR1, msg, n)
+	pubs, sigs, _, err := initCHECKMULTISIG(msg, n)
 	require.NoError(t, err)
 
 	pubs = subSlice(pubs, ik)
@@ -97,8 +89,8 @@ func initCHECKMULTISIGVM(t *testing.T, isR1 bool, n int, ik, is []int) *vm.VM {
 	return v
 }
 
-func testCHECKMULTISIGGood(t *testing.T, isR1 bool, n int, is []int) {
-	v := initCHECKMULTISIGVM(t, isR1, n, nil, is)
+func testCHECKMULTISIGGood(t *testing.T, n int, is []int) {
+	v := initCHECKMULTISIGVM(t, n, nil, is)
 
 	require.NoError(t, v.Run())
 	assert.Equal(t, 1, v.Estack().Len())
@@ -106,25 +98,21 @@ func testCHECKMULTISIGGood(t *testing.T, isR1 bool, n int, is []int) {
 }
 
 func TestECDSASecp256r1CheckMultisigGood(t *testing.T) {
-	testCurveCHECKMULTISIGGood(t, true)
+	testCurveCHECKMULTISIGGood(t)
 }
 
-func TestECDSASecp256k1CheckMultisigGood(t *testing.T) {
-	testCurveCHECKMULTISIGGood(t, false)
+func testCurveCHECKMULTISIGGood(t *testing.T) {
+	t.Run("3_1", func(t *testing.T) { testCHECKMULTISIGGood(t, 3, []int{1}) })
+	t.Run("2_2", func(t *testing.T) { testCHECKMULTISIGGood(t, 2, []int{0, 1}) })
+	t.Run("3_3", func(t *testing.T) { testCHECKMULTISIGGood(t, 3, []int{0, 1, 2}) })
+	t.Run("3_2", func(t *testing.T) { testCHECKMULTISIGGood(t, 3, []int{0, 2}) })
+	t.Run("4_2", func(t *testing.T) { testCHECKMULTISIGGood(t, 4, []int{0, 2}) })
+	t.Run("10_7", func(t *testing.T) { testCHECKMULTISIGGood(t, 10, []int{2, 3, 4, 5, 6, 8, 9}) })
+	t.Run("12_9", func(t *testing.T) { testCHECKMULTISIGGood(t, 12, []int{0, 1, 4, 5, 6, 7, 8, 9}) })
 }
 
-func testCurveCHECKMULTISIGGood(t *testing.T, isR1 bool) {
-	t.Run("3_1", func(t *testing.T) { testCHECKMULTISIGGood(t, isR1, 3, []int{1}) })
-	t.Run("2_2", func(t *testing.T) { testCHECKMULTISIGGood(t, isR1, 2, []int{0, 1}) })
-	t.Run("3_3", func(t *testing.T) { testCHECKMULTISIGGood(t, isR1, 3, []int{0, 1, 2}) })
-	t.Run("3_2", func(t *testing.T) { testCHECKMULTISIGGood(t, isR1, 3, []int{0, 2}) })
-	t.Run("4_2", func(t *testing.T) { testCHECKMULTISIGGood(t, isR1, 4, []int{0, 2}) })
-	t.Run("10_7", func(t *testing.T) { testCHECKMULTISIGGood(t, isR1, 10, []int{2, 3, 4, 5, 6, 8, 9}) })
-	t.Run("12_9", func(t *testing.T) { testCHECKMULTISIGGood(t, isR1, 12, []int{0, 1, 4, 5, 6, 7, 8, 9}) })
-}
-
-func testCHECKMULTISIGBad(t *testing.T, isR1 bool, isErr bool, n int, ik, is []int) {
-	v := initCHECKMULTISIGVM(t, isR1, n, ik, is)
+func testCHECKMULTISIGBad(t *testing.T, isErr bool, n int, ik, is []int) {
+	v := initCHECKMULTISIGVM(t, n, ik, is)
 
 	if isErr {
 		require.Error(t, v.Run())
@@ -136,45 +124,41 @@ func testCHECKMULTISIGBad(t *testing.T, isR1 bool, isErr bool, n int, ik, is []i
 }
 
 func TestECDSASecp256r1CheckMultisigBad(t *testing.T) {
-	testCurveCHECKMULTISIGBad(t, true)
+	testCurveCHECKMULTISIGBad(t)
 }
 
-func TestECDSASecp256k1CheckMultisigBad(t *testing.T) {
-	testCurveCHECKMULTISIGBad(t, false)
-}
-
-func testCurveCHECKMULTISIGBad(t *testing.T, isR1 bool) {
-	t.Run("1_1 wrong signature", func(t *testing.T) { testCHECKMULTISIGBad(t, isR1, false, 2, []int{0}, []int{1}) })
-	t.Run("3_2 wrong order", func(t *testing.T) { testCHECKMULTISIGBad(t, isR1, false, 3, []int{0, 2}, []int{2, 0}) })
-	t.Run("3_2 duplicate sig", func(t *testing.T) { testCHECKMULTISIGBad(t, isR1, false, 3, nil, []int{0, 0}) })
-	t.Run("1_2 too many signatures", func(t *testing.T) { testCHECKMULTISIGBad(t, isR1, true, 2, []int{0}, []int{0, 1}) })
+func testCurveCHECKMULTISIGBad(t *testing.T) {
+	t.Run("1_1 wrong signature", func(t *testing.T) { testCHECKMULTISIGBad(t, false, 2, []int{0}, []int{1}) })
+	t.Run("3_2 wrong order", func(t *testing.T) { testCHECKMULTISIGBad(t, false, 3, []int{0, 2}, []int{2, 0}) })
+	t.Run("3_2 duplicate sig", func(t *testing.T) { testCHECKMULTISIGBad(t, false, 3, nil, []int{0, 0}) })
+	t.Run("1_2 too many signatures", func(t *testing.T) { testCHECKMULTISIGBad(t, true, 2, []int{0}, []int{0, 1}) })
 	t.Run("gas limit exceeded", func(t *testing.T) {
-		v := initCHECKMULTISIGVM(t, isR1, 1, []int{0}, []int{0})
+		v := initCHECKMULTISIGVM(t, 1, []int{0}, []int{0})
 		v.GasLimit = fee.ECDSAVerifyPrice - 1
 		require.Error(t, v.Run())
 	})
 
 	msg := []byte("NEO - An Open Network For Smart Economy")
-	pubs, sigs, _, err := initCHECKMULTISIG(isR1, msg, 1)
+	pubs, sigs, _, err := initCHECKMULTISIG(msg, 1)
 	require.NoError(t, err)
 	arr := stackitem.NewArray([]stackitem.Item{stackitem.NewArray(nil)})
 
 	t.Run("invalid message type", func(t *testing.T) {
-		v := initCheckMultisigVMNoArgs(isR1)
+		v := initCheckMultisigVMNoArgs()
 		v.Estack().PushVal(sigs)
 		v.Estack().PushVal(pubs)
 		v.Estack().PushVal(stackitem.NewArray(nil))
 		require.Error(t, v.Run())
 	})
 	t.Run("invalid public keys", func(t *testing.T) {
-		v := initCheckMultisigVMNoArgs(isR1)
+		v := initCheckMultisigVMNoArgs()
 		v.Estack().PushVal(sigs)
 		v.Estack().PushVal(arr)
 		v.Estack().PushVal(msg)
 		require.Error(t, v.Run())
 	})
 	t.Run("invalid signatures", func(t *testing.T) {
-		v := initCheckMultisigVMNoArgs(isR1)
+		v := initCheckMultisigVMNoArgs()
 		v.Estack().PushVal(arr)
 		v.Estack().PushVal(pubs)
 		v.Estack().PushVal(msg)
diff --git a/pkg/core/interop/crypto/interop.go b/pkg/core/interop/crypto/interop.go
index 6c7b465fb..8a06c7fc3 100644
--- a/pkg/core/interop/crypto/interop.go
+++ b/pkg/core/interop/crypto/interop.go
@@ -7,13 +7,11 @@ import (
 
 var (
 	ecdsaSecp256r1CheckMultisigID = interopnames.ToID([]byte(interopnames.NeoCryptoCheckMultisigWithECDsaSecp256r1))
-	ecdsaSecp256k1CheckMultisigID = interopnames.ToID([]byte(interopnames.NeoCryptoCheckMultisigWithECDsaSecp256k1))
 	neoCryptoCheckSigID           = interopnames.ToID([]byte(interopnames.NeoCryptoCheckSig))
 )
 
 var cryptoInterops = []interop.Function{
 	{ID: ecdsaSecp256r1CheckMultisigID, Func: ECDSASecp256r1CheckMultisig},
-	{ID: ecdsaSecp256k1CheckMultisigID, Func: ECDSASecp256k1CheckMultisig},
 	{ID: neoCryptoCheckSigID, Func: ECDSASecp256r1CheckSig},
 }
 
diff --git a/pkg/core/interop/interopnames/names.go b/pkg/core/interop/interopnames/names.go
index 85ad88278..8e043beba 100644
--- a/pkg/core/interop/interopnames/names.go
+++ b/pkg/core/interop/interopnames/names.go
@@ -38,7 +38,6 @@ const (
 	SystemStoragePut                         = "System.Storage.Put"
 	SystemStorageAsReadOnly                  = "System.Storage.AsReadOnly"
 	NeoCryptoCheckMultisigWithECDsaSecp256r1 = "Neo.Crypto.CheckMultisigWithECDsaSecp256r1"
-	NeoCryptoCheckMultisigWithECDsaSecp256k1 = "Neo.Crypto.CheckMultisigWithECDsaSecp256k1"
 	NeoCryptoCheckSig                        = "Neo.Crypto.CheckSig"
 )
 
@@ -79,6 +78,5 @@ var names = []string{
 	SystemStoragePut,
 	SystemStorageAsReadOnly,
 	NeoCryptoCheckMultisigWithECDsaSecp256r1,
-	NeoCryptoCheckMultisigWithECDsaSecp256k1,
 	NeoCryptoCheckSig,
 }
diff --git a/pkg/core/interops.go b/pkg/core/interops.go
index 064cdc777..4a91c0e95 100644
--- a/pkg/core/interops.go
+++ b/pkg/core/interops.go
@@ -76,7 +76,6 @@ var systemInterops = []interop.Function{
 
 var neoInterops = []interop.Function{
 	{Name: interopnames.NeoCryptoCheckMultisigWithECDsaSecp256r1, Func: crypto.ECDSASecp256r1CheckMultisig, Price: 0, ParamCount: 3},
-	{Name: interopnames.NeoCryptoCheckMultisigWithECDsaSecp256k1, Func: crypto.ECDSASecp256k1CheckMultisig, Price: 0, ParamCount: 3},
 	{Name: interopnames.NeoCryptoCheckSig, Func: crypto.ECDSASecp256r1CheckSig, Price: fee.ECDSAVerifyPrice, ParamCount: 2},
 }
 
diff --git a/pkg/interop/crypto/crypto.go b/pkg/interop/crypto/crypto.go
index 3d605b90a..2cea41e56 100644
--- a/pkg/interop/crypto/crypto.go
+++ b/pkg/interop/crypto/crypto.go
@@ -14,12 +14,6 @@ func ECDSASecp256r1CheckMultisig(msg []byte, pubs []interop.PublicKey, sigs []in
 	return neogointernal.Syscall3("Neo.Crypto.CheckMultisigWithECDsaSecp256r1", msg, pubs, sigs).(bool)
 }
 
-// ECDSASecp256k1CheckMultisig checks multiple ECDSA signatures at once. It uses
-// `Neo.Crypto.CheckMultisigWithECDsaSecp256k1` syscall.
-func ECDSASecp256k1CheckMultisig(msg []byte, pubs []interop.PublicKey, sigs []interop.Signature) bool {
-	return neogointernal.Syscall3("Neo.Crypto.CheckMultisigWithECDsaSecp256k1", msg, pubs, sigs).(bool)
-}
-
 // CheckSig checks that sig is correct script-container's signature for a given pub
 // (serialized public key). It uses `Neo.Crypto.CheckSig` syscall.
 func CheckSig(pub interop.PublicKey, sig interop.Signature) bool {