The 'Good Will Hunting' star, 63, was found dead yesterday of an apparent suicide.
Hailing his stage performances as the best ones, Amitabh Bachchan tweeted, "Lost in person Robin Williams... his versatility extraordinary, his best though to me was his stage stand-up solo performances!!"
Shah Rukh Khan called Williams' his captain, referring to the actor's inspiring role in film 'Dead Poets Society' (1989) while quoting Oscar Wilde.
"'To have no yesterday, and no to-morrow. To forget time, to forgive life, to be at peace'... may death be so for My Captain. RIP Mr Williams," the star wrote on his Twitter page.
Earlier in the day, other celebrities like Kamal Haasan, Arjun Kapoor, Abhishek Bachchan, Shabana Azmi, Abhay Deol, Farah Khan, Shekhar Kapur took to the micro-blogging site to express their sadness over Williams' demise.
Haasan, whose 'Chachi 420' was said to be inspired by Williams 'Mrs Doubtfire', said, "If the alleged story about his suicide is true then I dislike him for ending his life before his due date of expiry. That's a cop out that I don't expect of an artist of his calibre. Same applies to my Indian idol Guru Dutt".
Abhishek remembered him for his funny antics in films and wrote, "Oh captain, my... Terrible news about the passing of one of my favourite actors. Mr Robin Williams. This is the 1st time he made anyone cry."
Azmi and Abhay call his death a major loss to the films.
"Robin Williams. What a loss! You leave behind a vacuum difficult to fill but your remarkable body of work will continue to inspire. RIP," Shabana tweeted.
Abhay said, "Philip Seymour Hoffman, Zohra Sehgal, Robin Williams. The world's a better place because they lived. RIP."
"RIP Robin Williams. You will always remain in my memory as Mrs Doubtfire... Hope you find happiness up there you mad genius...," Arjun posted.
"Robin Williams... This seems like a personal loss... What a sad start to the day... So much to learn, much to mourn... #RIPRobinWilliams," Richa Chadha tweeted.
Shekhar Kapur questions the alleged suicide committed by the actor.
"The man that brought us so much laughter and joy committed suicide Who knows the internal conflicts of the creative mind #RIPRobinWilliams," he tweeted.
Farah tweeted, "Oh God!! How do you tell your kids Mrs Doubtfire has died! RIP Robin Williams.. Thank you for the laughter in the movies!"
Farhan Akhtar and Sidharth Malhotra thanked the legendary actor for entertaining them from decades.
"Robin Williams. Thank you for the decades of entertainment. RIP," Farhan wrote.
Sidharth said, "Sad to hear about Robin Williams-RIP and thank you for all the laughs."
"Woke up to the awful and tragic news of Mr Robbin Williams. He touched our hearts through so many wonderful characters. RIP captain o captain," Arjun Rampal tweeted.