More than 80 percent of China's listed coal companies suffered a drop in net profit in the first half of this year, amid increasing imports and soft demand, the China National Coal Association said.

Among 40 listed coal producers inChina, the first-half net profit of 32 companies declined, with 25 companies falling more than 40 percent year-on-year, the CNCA said.

Experts said weak foreign and domestic demand, compounded by oversupply, has had widespread financial implications for producers.

As coal prices face further drops this summer, because of the increase of hydropower generation, very few coal enterprises have witnessed growth in net profit.

Coal output fell 3.5 percent year-on-year to 2.13 billion tons, with sales down 3.9 percent to 2.07 billion tons, according to the CNCA.

Pressures on the industry led coal-producing regions such as Shanxi province, the Inner Mongolia autonomous region, Shandong province and Henan province, to roll out measures to help companies that had to cut or suspend production.