Sathya Sai Baba died after a prolonged illness in Andhra Pradesh's Puttaparthi town at the age of 85.
"Sai Baba RIP. My condolences to all his followers, " actor R. Madhavan posted on micro-blogging site Twitter.
Actor Rana Daggubati tweeted: "RIP....Sathya Sai Baba. My condolences to all his followers."
"Just heard that Baba left his body...my heart bleeds for his followers..my sincere condolences, " director Ram Gopal Varma said.
Director and producer Madhur Bhandarkar's post read: "Sad to hear about the demise of Sathya Sai Baba. He was an inspiration for many. Such an enlightened soul."
Delhi-based designer Arpan Vohra said he felt blessed that he had earlier got a chance to go to Puttaparthi and seek Sai Baba's blessings.
"Jai Satya Sai Baba. God Bless his soul. I had the honour of going to Puttaparthi with my family to seek his blessings and met him. It was great to receive vibhuthi (sacred ashes) from him. He will be remembered for his noble deeds, " he told.
Designer Varija Bajaj said: "May his message live and guide us forever."
Hyderabad-based designer Abhi Jain said: "I am speechless and don't know how to react as this news came as a thunderstorm for me."
Accessory designer Sonal Chavan says she will keep a fast for the whole day as a mark of respect.
"I was a big follower of the person and it's an unfortunate truth to accept. I will be keeping a fast for the whole day and plan not to take even a sip of water, " she said.
"What a coincidence. Today is the birth anniversary of one of best cricketers of the world and on the other hand, we lost our spiritual guru. This news has came as a shock for me and I am blank, " Kolkata-based designer Joy Mitra said, referring to the 38th birthday of Sachin Tendulkar Sunday.
Mumbai-based model Aryan Baruah said: "May his soul rest in peace and God bless him forever."
Sai Baba, revered by millions in India and abroad, was suffering from multi-organ dysfunction. He breathed his last at 7.40 a.m. Sunday at the Sathya Sai super-speciality hospital in Puttaparthi, where he was admitted March 28 with cardiac problems.
His body will be kept at Prashanti Nilayam - his ashram in Puttaparthi - for two days to enable devotees to have a "last darshan".