The benchmark index gained over 68 points in early trade on the Bombay Stock Exchange on Mumbai on buying by funds in heavy-weight steel and auto stocks.
The BSE 30-share index, which gained 129 points in previous day's trading, added 67.40 points at 15,189.14 in the first five minute of trade.
Similarly, the wide-base National Stock Exchange's Nifty was up by 6.20 points at 4418.50 .
Marketmen said major support to the market came from some of the heavy weight stocks in metal and auto sectors.
A better trend in Asian stock markets also boosted the market sentiment, they added.