diff --git a/CHANGELOG.md b/CHANGELOG.md
index f1765bd669..1c2d87f40d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,7 @@
 * [\#8](https://github.com/line/wasmd/pull/8) Bump line/lbm-sdk to a7557b1d10
 
 ### Bug Fixes
+* [\#12](https://github.com/line/wasmd/pull/12) fix not to register wrong codec in `x/wasmplus`
 
 ### Breaking Changes
 
diff --git a/x/wasmplus/types/codec.go b/x/wasmplus/types/codec.go
index 71237b391b..9e3073be6f 100644
--- a/x/wasmplus/types/codec.go
+++ b/x/wasmplus/types/codec.go
@@ -16,7 +16,7 @@ import (
 
 // RegisterLegacyAminoCodec registers the account types and interface
 func RegisterLegacyAminoCodec(cdc *codec.LegacyAmino) { //nolint:staticcheck
-	legacy.RegisterAminoMsg(cdc, &MsgStoreCodeAndInstantiateContract{}, "wasm/StoreCodeAndInstantiateContract")
+	legacy.RegisterAminoMsg(cdc, &MsgStoreCodeAndInstantiateContract{}, "wasm/MsgStoreCodeAndInstantiateContract")
 
 	cdc.RegisterConcrete(&DeactivateContractProposal{}, "wasm/DeactivateContractProposal", nil)
 	cdc.RegisterConcrete(&ActivateContractProposal{}, "wasm/ActivateContractProposal", nil)
diff --git a/x/wasmplus/types/tx.go b/x/wasmplus/types/tx.go
index 7589343343..7d425b342b 100644
--- a/x/wasmplus/types/tx.go
+++ b/x/wasmplus/types/tx.go
@@ -3,12 +3,10 @@ package types
 import (
 	sdk "github.com/line/lbm-sdk/types"
 	sdkerrors "github.com/line/lbm-sdk/types/errors"
-
-	wasmtypes "github.com/line/wasmd/x/wasm/types"
 )
 
 func (msg MsgStoreCodeAndInstantiateContract) Route() string {
-	return wasmtypes.RouterKey
+	return RouterKey
 }
 
 func (msg MsgStoreCodeAndInstantiateContract) Type() string {
@@ -51,7 +49,7 @@ func (msg MsgStoreCodeAndInstantiateContract) ValidateBasic() error {
 }
 
 func (msg MsgStoreCodeAndInstantiateContract) GetSignBytes() []byte {
-	return sdk.MustSortJSON(wasmtypes.ModuleCdc.MustMarshalJSON(&msg))
+	return sdk.MustSortJSON(ModuleCdc.MustMarshalJSON(&msg))
 }
 
 func (msg MsgStoreCodeAndInstantiateContract) GetSigners() []sdk.AccAddress {
diff --git a/x/wasmplus/types/tx_test.go b/x/wasmplus/types/tx_test.go
index 6b00495595..c7f1c134a1 100644
--- a/x/wasmplus/types/tx_test.go
+++ b/x/wasmplus/types/tx_test.go
@@ -9,6 +9,7 @@ import (
 	"github.com/stretchr/testify/require"
 
 	sdk "github.com/line/lbm-sdk/types"
+	"github.com/line/lbm-sdk/x/auth/legacy/legacytx"
 
 	wasmTypes "github.com/line/wasmd/x/wasm/types"
 )
@@ -135,3 +136,37 @@ func TestNewMsgStoreCodeAndInstantiateContractGetSigners(t *testing.T) {
 	bytes := sdk.MustAccAddressFromBech32(res[0].String())
 	require.Equal(t, "696e707574313131313131313131313131313131", fmt.Sprintf("%v", hex.EncodeToString(bytes)))
 }
+
+func TestMsgJsonSignBytes(t *testing.T) {
+	const myInnerMsg = `{"foo":"bar"}`
+	specs := map[string]struct {
+		src legacytx.LegacyMsg
+		exp string
+	}{
+		"MsgInstantiateContract with every field": {
+			src: &MsgStoreCodeAndInstantiateContract{Sender: "sender1", WASMByteCode: []byte{89, 69, 76, 76, 79, 87, 32, 83, 85, 66, 77, 65, 82, 73, 78, 69},
+				InstantiatePermission: &wasmTypes.AccessConfig{Permission: wasmTypes.AccessTypeAnyOfAddresses, Addresses: []string{"address1", "address2"}},
+				Admin:                 "admin1", Label: "My", Msg: wasmTypes.RawContractMessage(myInnerMsg), Funds: sdk.Coins{{Denom: "denom1", Amount: sdk.NewInt(1)}}},
+			exp: `
+{
+	"type":"wasm/MsgStoreCodeAndInstantiateContract",
+	"value": {"admin":"admin1","funds":[{"amount":"1","denom":"denom1"}],"instantiate_permission":{"addresses":["address1","address2"],
+		"permission":"AnyOfAddresses"},"label":"My","msg":{"foo":"bar"},"sender":"sender1","wasm_byte_code":"WUVMTE9XIFNVQk1BUklORQ=="}
+}`,
+		},
+		"MsgInstantiateContract with minimum field": {
+			src: &MsgStoreCodeAndInstantiateContract{},
+			exp: `
+{
+	"type":"wasm/MsgStoreCodeAndInstantiateContract",
+	"value": {"funds":[]}
+}`,
+		},
+	}
+	for name, spec := range specs {
+		t.Run(name, func(t *testing.T) {
+			bz := spec.src.GetSignBytes()
+			assert.JSONEq(t, spec.exp, string(bz), "raw: %s", string(bz))
+		})
+	}
+}