The man, who has not yet been named, was in the bedroom of his apartment in the Tarelton area when the fire broke out shortly after 8am.
It was spotted by the man’s son and his family who lived in a house adjacent to the apartment.
They had built the annex onto their house so that they could be closer to him and look after him, according to gardaí.
Fire crews from Dunmanway and Macroom fought the blaze, which is thought to have started in the bedroom.
The man was pronounced dead at the scene. His body was later taken to Cork University Hospital for a post mortem.
It is thought the blaze may have been caused by an electric light in the bedroom.
Gardaí at Macroom as well as the fire brigade sealed off the scene for forensic examination while they tried to identify the cause.
Superintendent Vincent Duggan said that based on a preliminary examination of the scene gardaí did not believe there were any suspicious circumstances behind the blaze.
“It is very sad for the man’s family,” he added.
Gardaí were yesterday withholding the man’s name to allow his family time to notify relatives in his native Germany. He had been living in Ireland for several years.
His family in Ireland were being comforted by neighbours.
Meanwhile, fire crews yesterday morning had to deal with a small blaze on an ambulance in Macroom.
It is understood the fire was caused by an electrical fault. No one was injured in the incident.