Just for knowledge

This may attract section 115BB of Income Tax Act, 1961 which deals with income from winnings from lotteries, crosswords, puzzles, card games, races (other than owning & maintaining horse races) or any kind of gambling or betting of any form or nature.

Tax @ 30% is applicable in such cases.

Vikas Sir,

 

Isn't it applicable for income in India while Rahul is asking for Income from Outside India. Is the same applicable for Income outside India? 

yes for a resident and ordinary resident it is

it is taxable. on other side provisions in DTAA between india and that country should also be considered

First of all begin with the Residential Status of the assessee.
If he proves to be a resident then global income is taxable in his hands.
Now assessee has winjings from Casino abroad, So he must have received the amount after necessary deduction of Taxes eg TDS in India.
This income is again subject to Tax in India.
Refer Double Taxation avoidance rules to know how assessee need not pay the Tax again on Income which has already been Taxed abroad.