The man, who was in his 40s, was found outside a house at Malin Head around 2am.
Gardai had called to the scene of the fire after it had been reported just after midnight.
Fire tenders from Buncrana and Carndonagh attended the blaze in the townland of Carnmalin.
The man’s body was found at the rear of the house.
A full Garda examination of the scene has been launched to determine the cause of the blaze and the conditions in which the man died.
His identity has not yet been released.