The fires have been fanned by strong winds from a distant hurricane, destroying hundreds of buildings and burning some areas to the ground.
Thousands of people have been forced to evacuate their homes and a state of emergency has been declared.
A huge search and rescue operation is under way, with some people still unaccounted for.
“We barely made it out in time,” Kamuela Kawaakoa, who fled to an evacuation shelter on Tuesday with his partner and six-year-old son, told the Associated Press.
“It was so hard to sit there and just watch my town burn to ashes and not be able to do anything,” he said. “I was helpless.”
Five evacuation shelters have been opened on Maui and officials earlier said they were “overrun” with people. The island is a popular tourist destination and visitors have been urged to stay away.
“This is not a safe place to be,” Hawaii Lt Governor Sylvia Luke told reporters. “We have resources that are being taxed.”
Firefighters are still battling active fires, with helicopters dropping water on the blazes from above.
“As the firefighting efforts continue, 36 total fatalities have been discovered today amid the active Lahaina fire,” the Maui county government said in a statement.
Lahaina, a resort city and the main tourist destination on the island, has been devastated by the fire and images show huge areas have been burnt down.
“We just had the worst disaster I’ve ever seen. All of Lahaina is burnt to a crisp. It’s like an apocalypse,” resident Mason Jarvi told Reuters. He showed the agency images of the city’s destroyed and blackened waterfront.
Mr Jarvi said he suffered burns after riding through the flames on his bike to save his dog.
