The non-profit says Janet Ferreira was last seen on July 5. The 15-year-old may be traveling with a man in the Fresno or San Jose areas.
Ferreira is 5-foot-2, about 140 pounds and has a tattoo of a dove with the name "Guadalupe" written below it on her right shoulder blade.
Anyone with information is asked to call 1-800-THE-LOST.