Firefighters responded around 10:00 p.m. Saturday to a home at 3122 Ch. Wilson in the Municipality of Pontiac, between Highway 148 and the Gatineau River.
When they arrived, the structure was already engulfed in flames, officials said.
The homeowners, who lived on the main floor, escaped and called 911. But their tenants, who lived in the basement, did not make it out of the building.
Their bodies were found by firefighters after the blaze was knocked down. Officials have not disclosed their identities.
Fire officials continue to investigate the cause of the fire.