The 30-share barometer, which had climbed almost 505 points in the previous two sessions, rose by another 55.26 points, or 0.32 per cent, to 17,198.94.
All the sectoral indices led by heathcare, banking and consumer durables were trading in the positive zone with gains of up to 0.85 per cent.
The wide-based National Stock Exchange index Nifty also moved up by 15.05 points, or 0.29 per cent, to 5,214.85.
Brokers said optimistic buying by funds as well as retail investors ahead of RBI's first quarter policy review later in the day today buoyed the trading sentiment.
Besides, a firm trend in the Asian markets on speculation European Union policy makers will take action to ease the region's debt crisis, they said.
In Asian region, the Japan's Nikkei was up 0.51 per cent, while Hong Kong's Hang Seng gained 0.30 per cent in the morning trade today.