The three miners' bodies were found at 23:30 Kiev time [20:30 p.m. GMT] on Wednesday in the Dobropolskaya mine in the Donbass region in eastern Ukraine. The preliminary cause of death is poisoning by a mixture of gases, the ministry said.
At least 13 people were killed in after a gas leak in the Zasyadko coal mine in the same region earlier in the day.
Coal mining accidents are common in the ex-Soviet republic because of under-funding and poor maintenance. Six miners lost their lives in another mine blast in eastern Ukraine in August.
Thursday has been declared a day of morning in the mining region, and the deceased will be buried on Friday.
At least 40 miners were killed in another former Soviet republic, Kazakhstan, Wednesday and 25 miners died after a blaze broke out September 7 in a Russian pit in southern Siberia.
