The BSE index falls 0.27 percent while the 50-share NSE index is down 0.26 percent.
Banks such as ICICI Bank fall ahead of inflation data, to be released around 11.30 IST (0600 GMT).
ICICI Bank falls 0.8 percent while HDFC Bank is down 0.9 percent.
A Reuters poll forecast the wholesale price index, India's main inflation gauge, rose an annual 7.7 percent, faster than 7.55 percent in August and well above the central bank's comfort level of 4-5 percent.
Reliance Industries gains 0.17 percent while Axis Bank is up 0.36 percent ahead of their July-September earnings later in the day.