Gregory Massaro, 62, was trapped on the second floor after the fire broke out shortly after 5:30 a.m. at the corner of Gordon and Chamberlain avenues, authorities said.
His 89-year-old mother, who lives on the first floor, was rescued by firefighters who found her on a couch, responders said.
She was taken to St. Joseph's Regional Medical Center as a precaution, Passaic County Prosecutor Camelia M. Valdes and Totowa Police Chief Robert Coyle said in a joint release.
No other injuries were reported, they said, adding that an investigation was being conducted to officially determine the cause.
A neighbor walking a dog saw the house on fire and called 911, responders said.
Although the main body of the blaze was initially knocked down in a little over an hour, firefighters had to contend with flames in the walls and ceiling.
The fire was declared under control nearly three hours after it broke out.
Mutual aid at the scene included firefighters from Woodland Park and Little Falls, with Paterson and Wayne providing coverage for the town.
The Passaic County Prosecutor’s Office responded, along with the Passaic County Sheriff’s Office, which collected evidence.
Click here to follow Daily Voice Wyckoff-Franklin Lakes and receive free news updates.