Victoria Police say officers were called to the home at Whittington, in Geelong, around 8.30pm on Saturday to find 36-year-old father-of-five Daniel Surtees with severe burns.
Paramedics arrived soon afterwards and took Surtees to hospital, where he died on Sunday.
The police arson squad have charged his 33-year-old wife of four years Angela O'Brien with murder.
An armchair inside the family home where the father-of-five is believed to have been sitting was found completely charred after being set alight.
Nine News footage from the scene showed the blaze reached the walls and ceiling, damaging the home's interior.