London-based steel tycoon Lakshmi Mittal has been ranked as India's wealthiest person for a fourth year by Forbes Asia magazine.
Mr Mittal was born to a poor family in Rajasthan in 1950
It put Mr Mittal's fortune at $51bn (£25bn), double last year's level.
The net worth of India's 40 richest people now totals $351bn, with the top three alone worth more than China's top 40, who have a net worth of $120bn.
India now has 54 billionaires, 18 more than last year, and they were helped by stock market gains and a strong rupee.
The stock market has roared 53% higher in the past year, and a rupee has appreciated 12% during the same period, Forbes Asia said.
Mukesh Ambani of Reliance Industries is snapping at Mr Mittal's heels in second place.
His net worth grew at a faster pace than Mr Mittal's last year to a total of $49bn.
Mr Ambani's estranged brother, Anil, ranks third, with his net worth rising by $30.2bn to $45bn.
Kushal Pal Singh is fourth on list with a net worth of $35bn, making him the world's richest real-estate developer.
Mr Singh's wealth has more than tripled from the $10bn he had last year after his company, DLF, listed on the stock market in June this year and its stock surged 60% in value.
Dropping one place to fifth position is Azim Premji, the head of technology giant Wipro who is currently valued at $14.8bn, up from $14bn last year.
Forbes began compiling the list in 2004.