Teton County authorities confirmed 33-year-old George Hoffman was killed when a fire ripped through his father's log home near Victor early Monday.
His father, Michael Hoffman, escaped with minor injuries.
The Teton County Fire District received a 911 call at 2:30 a.m. to the one-story home at 7722 N. 500 West, north of town.
Officials said the home was burning too hot to allow them to enter safely and search for victims.
Michael Hoffman said there was so much smoke, he had trouble finding a window to escape the fire at the back of the house.
The cause of the fire is under investigation, said Chief Bret Campbell.