The blaze broke out around 8:10 a.m. at the Royal Inn on the 100 block of South Delsea Drive in Glassboro.
Residents alerted management that they smelled smoke coming from the second floor.
Police were called and evacuated the building.
The Glassboro Fire Department extinguished the fire and found a man dead at the scene.
The victim has been identified as 52-year-old Walter White, who they say was an intermittent resident of the motel.
An autopsy by the Gloucester County Medical Examiner's Office is scheduled for Monday.
An investigation into the cause of the fire, by the Gloucester County Prosecutor's Office, the county Fire Marshal's Office and the Glassboro fire investigation unit, is continuing.
However, officials say evidence of smoking was found in the room.