The 30-share barometer moved down by 38.50 points, or 0.19 per cent, to 20,531.78 with banking, realty and capital goods sector stocks leading the fall.
The index had lost nearly 325 points in the past five sessions.
The wide-based National Stock Exchange index Nifty shed 8.45 points, or 0.14 per cent, to 6,092.65.
Brokers said selling by participants before the Reserve Bank’s second quarter monetary policy review today mainly led to the fall in stock prices.
Besides, a weakening trend in the Asian region also dampened the sentiments, they said.
In the Asian region, Japan’s Nikkei fell 0.14 points, and Hong Kong’s Hang Seng shed 0.11 per cent in early trade today.
The US Dow Jones Industrial Average ended 0.01 per cent lower in yesterday’s trade.