Deputies believe one of the drivers ran the red light on Mason Road at Colonial Parkway in west Harris County around midnight.
ABC13 crews were at the scene of the crash and saw airbags deployed in the deputy's vehicle.
Investigators said the deputy had her lights and siren on while on her way to a call about a stabbing.
HCSO said a woman in her 60s was also driving down Mason Road when the two collided. There was a red light, but it's unclear who ran it.
"There was a collision at the intersection. The patrol vehicle continued to travel westbound and struck a tree. The other driver came to rest in the intersection," Dashana Cheek with HCSO said.
Both the deputy and the other driver were taken to the hospital and are expected to be OK.