The body of the 58-year-old was discovered by fire officers after they fought the blaze.
He was named as James Cahillane, an electrician who lived alone at Ardraw, Beaufort, Co Kerry.
Gardaí have established he arrived by taxi at his home shortly before midnight.
Emergency services had been alerted by a neighbour who heard a loud bang shortly after 2am.
The three-bedroom bungalow was engulfed in flames by the time they arrived at the scene, which is located between Killarney and Killorglin.
Three units of the fire service were at the scene for nearly six hours.
The man was found in the hallway of the house, which was completely gutted.
The scene was sealed to allow gardaí conduct a technical examination.
The man’s remains were removed to Kerry General Hospital in Tralee for an autopsy to be carried out.