The accident came just a day after another workplace tragedy at a quarry in Northwest China's Shaanxi Province killed 12 people and injured 11 others.
One newspaper report said the mining accident was the third fatal gas explosion at the same mine in two years, according to the Associated Press.
Rescuers pumped water into the state-owned Jianxin Coal Mine to reduce the dust kicked up by the blast and lower the temperature for continuing salvage operations.
Meng Jianzhu, the Communist Party secretary of Jiangxi province, called on investigators to "conscientiously seek the cause of the explosion and learn some safety lessons from this tragedy," the Chinese news Web site Sina.com reported.
China's coal mines are the world's deadliest. More than 4,200 deaths have been reported so far this year in explosions, floods and cave-ins, according to AP. Lax safety rules and lack of fire and ventilation equipment are often blamed.