The 30-share barometer fell by 34.22 points, or 0.17 per cent, to 19,783.41. The index had lost 169.19 points yesterday.
Stocks of metal, banking, power, consumer durables and FMCG sectors declined due to profit-booking.
Similarly, the wide-based National Stock Exchange index Nifty fell by 13.75 points, or 0.22 per cent, to 5,988.10.
Brokers said apart from profit-booking by speculators, a weak trend in the Asian trade following overnight losses in the US market and in Europe, spurring selling, dampened the trading sentiment here.
In the Asian region, Japan's Nikkei Index was up by 0.18 per cent, while Hong Kong's Hang Seng index shed 0.11 per cent in early trade.
The US Dow Jones Industrial Average ended 0.17 per cent down in yesterday's trade.