The shooting happened just after 11 a.m. Thursday at a Chevron station in the 10400 block of Richmond at Rogerdale.
Video shows the shooter in a white or gray hoodie chasing the shooting victim through the parking lot, as bystanders watch as it all unfolds.
WATCH: Gunfire erupts outside Chevron in west Houston
Suddenly, the man raises his gun and fires two shots as the victim continues to run towards the front of the gas station.
The victim drops to the ground, and three more shots are fired at point-blank range. The gunman then takes off in a vehicle.
Houston police said the victim was taken to the hospital in unknown condition.
Follow TJ Parker on Facebook and Twitter.
HPD Major Assaults detectives are responding to a shooting outside a gas station in the 10400 block of Richmond. One person has been taken to an area hospital in unknown condition. #hounews— Houston Police (@houstonpolice) January 24, 2019