Hi I'm using Web3js and Ganache. I'm trying to send a serialized transaction but got the following error: (node:90923) UnhandledPromiseRejectionWarning: Error: Returned error: Invalid Signature . I've tried to switch Node version from 14.x.x to 12.x.x but no success. Not sure if the issue comes from Web3js or from @ethereumjs/tx...

Any ideas? Anyone experienced the same issue?


const EthereumTx  = require("@ethereumjs/tx").Transaction;

const URL = '';

const web3 = new Web3(URL);

const sendingAddress = '0xEF72345AD7616204dfD98D61716ba3222eb085eC';
const receivingAddress = '0x286164093efbaea6143F62212aA37A56Cd85362c';


// *********CREATE A TRANSACTION*********

const rawTransaction = {
    nonce: 0,
    to: receivingAddress,
    gasPrice: 20000000,
    gasLimit: 30000,
    value: 100,
    data: ""

// -- Step 7: Sign the transaction with the Hex value of the private key of the sender

const privateKeySender = 'PRIVATE KEY';
const privateKeySenderHex = new Buffer.from(privateKeySender, 'hex');
const transaction = new EthereumTx(rawTransaction);
// console.log('transaction', transaction);

// // -- Step 8: Send the serialized signed transaction to the Ethereum network.

const serializedTransaction = transaction.serialize();
web3.eth.sendSignedTransaction('0x' + serializedTransaction.toString('hex'));
  • Did you try to replace 'PRIVATE KEY' with the private key provided by Ganache? Commented Jan 2, 2022 at 14:28
  • Hi @IsmailElMoudni yes of course :) the problem most likely happens in sendSignedTransaction method
    – Eloi
    Commented Jan 2, 2022 at 17:28

1 Answer 1


transaction.sign(privateKeySenderHex) return new object try:

const signedTx = transaction.sign(privateKeySenderHex);
const serializedTransaction = signedTx.serialize();

full example:

singTransaction({ privateKey, to, value }: ArgsSingTransaction) {
 const hexPrivatekey = Buffer.from(privateKey, 'hex');

 const gasPrice = 20000000000;
 const gasLimit = 6721975;
 const nonce = 0;

 const tx = new Tx({ to: to, value: value, gasPrice, gasLimit, nonce, });

 const signedTx = tx.sign(hexPrivatekey);

 const serializedTx = signedTx.serialize();

 return '0x' + serializedTx.toString('hex');

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