Police said the man, who is in his mid-40s to mid-50s, was walking along the service road when a vehicle struck him and kept going.
It wasn't clear what kind of vehicle hit the man.
Police said someone called 911 around 6:11 a.m., and when the Houston Fire Department arrived on the scene, they saw someone doing CPR on the man.
That person then left without providing information to firefighters, according to investigators. Police said it's unknown if this person had anything to do with the crash.
Police said there was some debris from the vehicle found in the area, and they are hoping that would help them identify it.
Anyone with information about what happened or the vehicle involved can call the Houston Police Department.