The dilapidated building on 8 Indian Mirror Street, saw a large crowd since early morning Sunday as news leaked out about Dutt's impending arrival.
Accompanied by Samajwadi Party general secretary Amar Singh and encircled by his private security guards, Dutt arrived in a bullet-proof car to cries of 'Munnnabhai zindabad' and 'Sanjay Dutt Zindabad'. He was immediately taken into the house, whose residents were eagerly waiting.
Dutt was taken to the room where Nargis was believed to have been born in 1929 to a muslim mother - Allahabad based singer Jaddanbai - and a Hindu father - Rawalpindi based Uttamchand Mohanchand.
Sanjay spent about ten minutes in the room all alone, and seemed overcome by nostalgia when he came out.
'It's a very emotional moment for me. Thanks to Amar Singhji, that he found the house,' said the actor - affectionately called Sanjubaba.
'I was in the room alone for 10 minutes remembering my mother. Thanks to Kolkata and the people of Kolkata,' he said, before leaving the spot.
He later left for Nalhati in Birbhum to address an election meeting.