Reliance Industries chairman Mukesh Ambani and NRI steel baron Lakshmi Mittal lead the pack of 24 Indians in the Forbes' list of world's richest people.
As many as 29 Indians lost their billionaire status entirely as India's stock market tumbled 44 per cent in the past year and the Indian rupee depreciated 18 per cent against the dollar.
Ranked at 7th position, Mukesh with a total wealth of $19.5 billion is the richest Indian in the list closely followed by Mittal whose worth as calculated by the magazine amounts to $19.3 billion. Mittal is at the 8th spot.
But both were among the biggest losers because of the economic downturn, Forbes said.
India no longer has maximum number of billionaires in Asia, ceding that title to China, which now has 28 richest people.
Mukesh's brother and industrialist Anil Ambani occupies third position among Indian billionaires with a total wealth of $10.1 billion.
Last year's biggest billionaire gainer Ambani is this year's biggest loser, the magazine said, adding that his fortune is down $32 billion, as shares in his Reliance Communications fell by two-thirds.
Number of telecom customers increased, but people used fewer minutes amid worldwide recession.
Besides India's economic slowdown, margins squeezed due to expensive expansion and increased competition led to fall in Anil's wealth, Forbes said, adding that his company also took a hit when estranged brother Mukesh helped derail its merger with South Africa's MTN last July.
His Reliance Power and Reliance Capital holdings fell too.
Steel titan Mittal lost $25.7 billion which brought down his wealth to $19.3 billion.
With steel prices down 75 per cent since last summer and heavy fines from a French antitrust investigation that found 10 companies guilty of price fixing in European steel markets, ArcelorMittal stock, which makes up bulk of his fortune, is at four-year low, the Forbes said.
The group posted $2.6 billion loss in most recent quarter announced plans to slow acquisitions, cut capital expenditures and pay down its debts and recently halved its dividend to 75 cents.
Bharti group chairman Sunil Mittal is the fourth richest man in India with a total wealth of $7.7 billion followed by Wipro's Azim Premji with a net worth of $5.7 billion.
Closely following him are Shashi and Ravi Ruia with net worth of $5.6 billion and Kushal Pal Singh with a total wealth of $5 billion.
Youngest among the billionaires are Malvinder and Shivinder Singh with a total estimated wealth of $2.6 billion and oldest is 77-year old Kushal Pal Singh.
While Mukesh Ambani leads the list, Anurag Dikshit, who is based in Gibraltar, just makes it with wealth of USD one billion.
Others who made it to the list include Kumar Birla ($4.2 billion), Adi Godrej and family (3.3 billion), Dilip Shanghvi (3 billion), Savitri Jindal (2.7 billion), G M Rao (2.1 billion), Micky Jagtiani (2 billion), Gautam Adani (1.8 billion), Indu Jain (1.8 billion) and Shiv Nadar (1.7 billion).
Cyrus Poonawalla (1.5 billion), Anil Agarwal (1.5 billion), Uday Kotak (1.2 billion), Kalanithi Maran (1.2 billion), Chandru Raheja (1.2 billion), Subhash Chandra (1.1 billion) and Anurag Dikshit (1 billion) also figure in the list.