Mr Mistry was at Bombay House to chair a board meeting of Indian Hotels, a Tata company of which he is chairman.
As soon as Mr Mistry arrived at Bombay House, photographers entered an area that was cordoned off, as they tried to photograph him.
The security personnel posted there stepped in and roughed up photographers from the Times of India, Mid-Day and Hindustan Times, also damaging their cameras.
A case of assault has been registered against six security personnel.
The Mumbai press club has condemned the incident and have demanded the arrest of the security guards.
In videos posted and shared by outraged people on social media, the security guards are seen pushing and beating the journalists.
A Tata spokesperson NDTV spoke to apologised for the incident and said the guards should have shown more restraint.
"We profusely apologize to the press corp and their families for this incident. We will ensure that such a situation does not recur," the Group said in a statement.
Cyrus Mistry was sacked as chairman last week by Tata Sons, the holding company of the $100 billion conglomerate, but continues to serve as chairman of several companies of the group.
He has made no indication so far that he will quit these posts.