He is survived by his wife Nina, daughter of Dhirubhai Ambani, son Arjun and daughter Nayantara.
Kothari, 53, was popularly known as Shyam Kothari among business circles. He breathed his last in Houston in the US where he had gone for treatment.
His funeral and a prayer meetings were held today in Chennai, sources close to the family said.
Reliance Industries Chairman Mukesh Ambani, his brother Anil Ambani, Bollywood Super Star Amitabh Bachchan, former Union Minister Praful Patel clad in white kurta paid their last respects to the deceased at the crematorium.
Kothari was heading H C Kothari group, which has interests in petrochemicals, sugar, biotechnology and private equity areas. The Group had launched the country's first mutual fund- the Pioneer Fund, which was later sold to Franklin Templeton.