It happened around 3am on Fairbanks North Houston at Tidwell.
Investigators say the driver was making a right turn from Tidwell onto northbound Fairbanks North Houston, but didn't yield to oncoming traffic.
That's when a big rig traveling north on Fairbanks North Houston hit the SUV, officials said. The 18-wheeler crossed the median and ended up on the southbound side of the road, facing traffic.
The SUV driver was seriously injured and taken by LifeFlight to an area hospital. It was unclear if the driver of the 18-wheeler suffered any injuries.