It happened around 12:30 a.m. Sunday on the 4400 block of Cottman Avenue.
Upon arrival, officers were met by a woman who stated that her 38-year-old husband, who had left the home a week prior, had returned and forcibly entered the home by kicking in both the front and back doors.
According to police, the woman says that once her husband was inside he began threatening her.
The woman then retrieved her handgun and fired, striking him in the upper right shoulder.
He was pronounced dead at the scene.
The incident remains under investigation.