The unnamed miner was 30 years old and is believed to have suffered pre-existing medical conditions.

Premier Annastacia Palaszczuk said he was from Blackwater but did not state what mine he worked at.

Palaszczuk said the miner tested positive to the virus post mortem and the man's partner was also showing symptoms.

"She has been transferred to the Rockhampton Hospital, where she's being isolated and further tests are being done," Palaszczuk said.

"Blackwater has never had a case of COVID before. Contact tracing is extensively underway."

Central Highlands Mayor Kerry Hayes told the ABC that workers who commuted from other Central Queensland communities or from outside the region could have brought the virus into Blackwater.

"A lot of the population there is engaged, either directly or indirectly, with the resource industry," Hayes said.

"Some of their contingency plans are staged around a positive test happening in their community.

"If they need to be activated, we'll do that."

Construction Forestry Mining and Energy Union district president Stephen Smyth said any death from COVID-19 was a terrible loss.

 "Our thoughts go out the family and friends," he said.

 "The union is continuing to work with members and mining companies to make sure mining workforces and communities are safe at work and at home.

 "We are urging all our members to maintain social distancing and hygiene practices, get tested in a fever clinic if they have any respiratory symptoms and continue to follow all advice from the Chief Health Officer.

"This is a sad reminder that we can't afford to be complacent about the threat posed by COVID-19 and we all need to maintain our vigilance."