An explosion occurred on Saturday in the Linjiazhuang coal mine in Jinzhong, a city in Shanxi province, China's main coal-producing region. The official Xinhua News Agency said investigators blamed the blast on airborne coal dust that caught fire.
The mine manager was in police custody, state television said on its midday national news.
Some 64 miners were in the mine at the time of the explosion and six escaped, according to Xinhua.
It said only one miner was rescued alive from the mine and that he was suffering from carbon-monoxide poisoning.
China's coal mines are the world's deadliest, with more than 5,000 deaths every year in explosions, fires and other disasters. Last month, a flood in another coal mine in Shanxi killed 56 miners.