The 30-share index, which had lost 207.43 points in the previous session, fell further by 194.19 points, or 1.11 per cent, to 17,167.91 as soon as the trading session commenced today.
In a similar fashion, the wide-based National Stock Exchange Nifty index declined by 62.65 points, or 1.19 per cent, to 5,158.40 within minutes of the opening bell.
Stocks of metal, realty, IT, capital goods, refinery, banking and auto companies remained under selling pressure and were mainly responsible for the Sensex's decline.
The trading sentiment remained bearish amid steady outflows of capital from the equity market in the wake of weak corporate earnings posted by Tata Steel and DLF.
Meanwhile, in the Asia region, Japan's Nikkei Index fell by 0.16 per cent, while Hong Kong's Hang Seng Index was up by 0.97 per cent in early trade today.