I am trying passport js with Google app email id. I am able to authenticate using gmail.com email id. But how can I authenticate if the email id is a google app id (google.com/a/companyname.com).

This is my code

var express = require('express');
var app = express();
var passport = require('passport');
var GoogleStrategy = require('passport-google').Strategy;

passport.use(new GoogleStrategy({
    returnURL: 'http://10.3.0.52:3000/auth/google/return',
    realm: 'http://10.3.0.52:3000/'
},
function(identifier, profile, done) {
    User.findOrCreate({
        openId: identifier
    }, function(err, user) {
        done(err, user);
    });
}
));

app.get('/auth/google', passport.authenticate('google'));

app.get('/auth/google/return', 
    passport.authenticate('google', {
        successRedirect: '/',
        failureRedirect: '/login'
    }));

app.get('/', function(req, res){
    res.writeHead(200);

    res.end("connected");

});

app.listen(process.env.PORT || 3000);

Your code is missing some vital parts:

...
passport.use(...); // this you have

// these are required as well.
app.use(passport.initialize());
app.use(passport.session());

// please read docs for the following two calls
passport.serializeUser(function(user, done) {
  done(null, user);
});

passport.deserializeUser(function(obj, done) {
  done(null, obj);
});
...

With those in place, I can log in using my Google App address just fine.

EDIT: it only works with Node 0.8 though, Node 0.10 gives an error. I think using passport-google-oauth is a better solution anyway. For that, you have to register your application with Google (here); after registration, you'll be supplied both the GOOGLE_CLIENT_ID and GOOGLE_CLIENT_SECRET codes which you can use.