Police say 14-year-old Elizabeth Romero was taken by her boyfriend, 19-year-old Eduardo Fabian Flores-Rosales, at about 2:30 p.m. on Wednesday.
Surveillance video from her high school shows Romero getting into her boyfriend's car. The CHP says he was last seen driving a 2001 to 2003 hunter green Ford Escape with temporary Washington registration. The vehicle is believed to have a roof rack and custom wheels.
Romero is described as a Hispanic girl standing 5 feet 3 inches tall, weighing 130 pounds with brown hair and brown eyes. She was last seen wearing white tank top, dark pants and was carrying a backpack and a pink purse, the CHP said.
Flores-Rosales is described as a Hispanic man standing 5 feet 9 inches tall, weighing 200 pounds with black hair and brown eyes.
The CHP says they may pass through California and the Bay Area while en route to Mexico.
Anyone with information is asked to contact the Kennewick Police Department at (509) 628-0333.
(Bay City News contributed to this report)