An explosion at the mine Monday killed six people and left 11 missing, just three days after a blast killed 28 workers and injured a further 13, state media reported.
The blasts occurred at the Babao mine operated by state group Tonghua Mining in the northeastern province of Jilin.
An official for Tonghua Mining told Agence France Presse that the two blasts occurred in the same mine, but he did not respond when asked why the mine had remained open after the first explosion on Friday.
The explosions follow a string of accidents at Chinese coal mines this year.
A March 12 explosion left 25 people dead at the Machang coal mine in Shuicheng county.
Another 13 miners died in an explosion in Panxian county on January 18, while a rock burst in northeast China last month left a further four assumed dead.
According to recent economic figures from the Chinese National Bureau of Statistics, last year’s coal mine death toll was down 33.75% on 2011, but the country’s safety record still remains one of the worst in the world.
Government efforts to reduce hazardous mines have resulted in the closure of more than 9000 small coal mines since 2006.
In September, Chinese authorities pledged to shut down 20,000 illegal and unsafe mines by 2015 following a string of deadly gas explosions and collapses.