The company's stock ended down 9.97 per cent at Rs 13.45, its lower circuit limit on the BSE.
At the NSE, Lanco Infra's scrip tumbled 9.76 per cent to Rs 13.40.
Lanco Infratech's net loss for the quarter ended March 31 widened to Rs 584.29 crore on account of drop in revenue and mounting losses in EPC and construction business.
The power company had reported a net loss of Rs 31.59 crore in the same period of previous year.
Revenue from EPC (engineering, procurement and construction) segment in the quarter was down by nearly 55 per cent to Rs 670.42 against Rs 1476 crore during the same period a year ago. The segment reported loss of Rs 376.21 crore in the last quarter of FY14, against Rs 335.59 profit before tax and interest during Q4 of FY13.
For the full year 2013-14, Lanco's loss widened to Rs 2,274 crore from Rs 1,070.2 crore in the last fiscal.