Snapping its four-day long rising streak, the 30-share barometer lost by 60.47 points, or 0.29 per cent, to 20,586.17 with metal, banking, consumer durables, IT and FMCG sector stocks succumbing to profit-booking.
The index had climbed 684 points yesterday to an almost three year high.
The wide-based National Stock Exchange index Nifty fell 8.75 points, or 0.14 per cent, to 6,106.80.
Brokers said fresh selling, mostly of profit-booking nature, by participants before the Reserve Bank's mid-quarter monetary policy review today, mainly attributed fall in stock prices.
In the Asian region, Japan's Nikkei up by 0.24 points in early trade, Hong Kong's exchange remained closed today.
The US Dow Jones Industrial Average ended 0.26 per cent lower in the previous session.