The California Highway Patrol says the crash happened about 5:40 pm on Tuesday on Highway 145 east of the I-5.
The SUV was heading south when it crossed over to the northbound lane and collided head-on with the truck.
The truck overturned and caught fire, killing one occupant, CHP officials say.
They do not yet know if there was anyone else was inside the truck.
The woman who was driving the SUV sustained moderate injuries and was transported to the Community Regional Medical Center.