Datta Phuge shot to the limelight in 2013 when he bought a shirt made with more than 3kg of gold and worth $250,000 (£186,943).
A money lender based in western Pune, Mr Phuge was called "the gold man".
Four persons have been detained for questioning. Police suspect a dispute over money have led to the murder.
The police said some 12 people attacked Mr Phuge, 48, in Pune on Thursday night.