Following the disappointing results, shares of the state-run firm started the trade on a weak note and as the trade progressed it further fell by 2.89 per cent to Rs 276.70 on BSE.
On NSE, the stock lost 2.99 per cent to Rs 276.55.
"Coal India's Q2 top-line was above our estimate, however, its bottom-line was slightly below our estimate," said Bhavesh Chauhan, Sr Research Analyst - Metals & Mining, Angel Broking.
Coal India yesterday reported a marginal drop in consolidated net profit at Rs 3,052.36 crore for the July-September quarter due to higher input cost and less e-auction realisation.
The world's largest coal miner posted a profit of Rs 3,078.08 crore in the second quarter of 2012-13.
Coal India net sales rose 5.75 per cent to Rs 15,411.49 crore from Rs 14,572.54 crore, Coal India had said.
Total expenses increased 8.38 per cent to Rs 13,112.45 crore. The bulk of the expenses were on employee benefits, on which the company spent Rs 6,974 crore.