Police said the victim was in a Cadillac near the Renaissance Airport Hotel about 12:30 p.m. when the car was sprayed with gunfire. A woman in the car was left unhurt.
The victim, 28-year-old Brian Johnson of Lancaster, was taken to Ronald Reagan UCLA Medical Center. He was pronounced dead about an hour later.
Authorities said Johnson, his girlfriend and his brother had gone to the hotel on Airport Boulevard and 96th Street to visit a friend from out of town.
The brother was in a rented car with the friend and Johnson was sitting in the Cadillac with his girlfriend when gunfire erupted.
"The brother who rented the car apparently saw two cars pull up with shooters and started screaming 'Get down, Get down," said Det. Mark Morgan. "Shots were fired and the victim was killed."
Johnson's brother was grazed by a bullet when he ran to get help. He took himself to the hospital and was treated and released.
A suspect was identified as a black man in his early 20s.
The motive for the shooting was unclear, authorities said. They said it might be a targeted hit.