It happened around 11:30pm when the victim and another man were driving on Northdale at Southbank when another car pulled up and someone started firing shots, hitting the passenger.
Authorities say it appears that the driver got into an argument with the person in the second car earlier in the day.
The victim was taken to the hospital where he later died. Houston police are investigating.
The gunman remains on the loose.
Slideshow archive | ABC13 wireless | Help solve crimes