The 30-share barometer, which gained 119.32 points in the previous session, was down by 220.70 points, or 1.37 per cent, at 15,844.72 within minutes of the opening bell today.
The wide-based National stock Exchange Nifty index also fell by 67.45 points, or 1.40 per cent, to 4,744.90. All the sectoral indices, led by metal, tech and banking stocks, were trading in the negative zone, with losses of up to 1.54 per cent.
Brokers said a fresh bout of selling by funds and retail investors, cashing in on the brief recovery of the equity markets yesterday amid a weak trend in global markets, weighed down the trading sentiment.
In addition, they said, expiry of monthly derivative contracts later this week and fresh concerns about the health of the global economy after a downward revision of the US growth rate in the third quarter of 2011.
Meanwhile, Hong Kong's Hang Seng index was down by 1.76 per cent in morning trade and Japan's Nikkei fell by 0.40 per cent. In the US, the Dow Jones Industrial Average shed 0.46 per cent yesterday.