"In all, 27 people were buried in the collapse of the gold mine. Twenty-five bodies were found and dug out but two could not be found" after the accident on Thursday near the southern city of Bambari, a police source said.
The mine in the town of Ndassima is under the control of former rebels of the Seleka movement who were operating illegally, police said.
A source close to the former rebels said he could not confirm whether the dead miners were Seleka members.
A collapse at the same mine last year claimed 62 lives.
Thousands of people began exploiting the Ndassima mine illegally after its owner, Canadian company Axmin, shut it down in 2011 because of security concerns in the conflict- riven country.
The gold reserves at the mine are estimated at about 3.6 million ounces, worth some USD 4.6 billion (3.5 billion euros) at current market prices.