The benchmark index failed to hold early gain and shed 18 points on Friday on emergence of profit selling by funds.
The BSE-30 share index, Sensex, which started higher by 9.39 points, fell down by 18.74 points at 14,480.50 in first five minutes of trade.
Similarly, the wide-based National Stock Exchange's Nifty lost 4.90 points at 4267.55.
Stock brokers said weakening trend in asian markets influenced the trading sentiment here.
They said a constant rise in share prices in last three trading sessions also attracted profit-selling at higher levels.