Police were called out just before 12:00 a.m. Monday to the 6200 block of Magnolia Street in East Mount Airy.
When officers arrived, they found the victim lying on his living room floor.
Family members told police there was a knock at the front door, the victim looked through a peep hole on the side of the door, and two shots were fired through that peep hole.
The victim was hit at least once in the face and was pronounced dead at the scene.
Homicide detectives and the crime scene unit were at the home early Monday gathering evidence.
There was no immediate word on a possible motive for the shooting.
The gunman remains at large.