Deputies assigned to the Marina Del Rey station responded to the shooting in the 5800 block of Holt Avenue at about 11:30 p.m., according to the Los Angeles County Sheriff's Department.
When they arrived, they found the victim with multiple gunshot wounds. He was pronounced dead at the scene.
Investigators say the man got into an argument at a party at a nearby residence. Video on social media shows a large house party in the area at the time.
When the victim left the party, he was confronted again by the suspect and a fight ensued. During the fight, the suspect shot the man.
A detailed suspect description was unavailable.
The victim was not identified.
An investigation is ongoing. Anyone with information on the shooting was urged to call the department's Homicide Bureau at 323-890-5500.