If you use Express (High performance, high class web development for Node.js), you can do this:

HTML:

<form method="post" action="/">

<input type="text" name="user[name]">

<input type="text" name="user[email]">

<input type="submit" value="Submit">

</form>

Javascript:

app.use(express.bodyParser();

app.post('/', function(request, response){

console.log(request.body.user.name);

console.log(request.body.user.email);

});