The officer was westbound on Greens Rd. He was headed to a call and had his lights and sirens on, officials said.
A sports utility vehicle was going south on the North Freeway feeder when it approached Green Rd., and then slammed into the officer's squad car.
Witnesses say the SUV ran a red light.
The officer and driver of the SUV both went to the Memorial Hermann Hospital with minor injuries. The officer had a cut to his head, officials said.
According to police, the blood alcohol content of the SUV driver will be tested.