The 30-share barometer, which had gained 187.50 points in the previous two sessions, fell by 74.56 points, or 0.35 per cent, to 21,176.56.
Stocks of FMCG, banking, IT and auto sectors led the fall.
Similarly, the National Stock Exchange index Nifty declined by 6.00 points, or 0.10 per cent, to 6,307.80.
Brokers said profit selling by funds amid a weak trend in the Asian region influenced the trading sentiment.
Among other Asian markets, Hong Kong's Hang Seng fell by 0.34 per cent while Japan's Nikkei was down 0.30 per cent in early trade today.