Fire crews were called to the blaze on the 1600 block of Haro Street at around 2 p.m. PT. The woman, who has not been identified, was already dead.
Randy Hebenton of the Vancouver Fire Department said fire crews only became aware of the woman's body once the smoke had cleared.
"They found a fire and heavily charged the suite with smoke. They extinguished the fire and tried to start to ventilate the smoke, which made visual a deceased person in the room," he said.
It is unclear whether the woman died before the fire broke out or whether she succumbed to the smoke and flames.
But residents of the government-subsidized housing, which is home to many elderly and disabled people, have expressed concerns that fire crews' ladders could not reach the 22nd floor of the building.
The Vancouver Fire Department has confirmed that since their ladders can only reach as far as the 10th or 11th floor, occupants of upper levels are usually expected to walk down the fire escape.
Police and fire investigators are not considering the death suspicious but it is under investigation.