Kristina Gutierrez was last seen March 20 about 3 p.m. when she left her home to walk the Oso Creek Trail.
Investigators say before she left, she had an argument with a relative on the phone.
Gutierrez is known to frequent the trail at Marguerite Parkway and La Paz, as well as nearby shopping centers, where she sometimes panhandles, according to authorities.
She is described as Hispanic, about 5 feet and 4 inches tall, weighing 150 pounds with green eyes and blond hair. She has a tattoo with the name "Charley" across her upper chest. She was last seen wearing a blue hooded sweatshirt, a white and burgundy shirt and blue jeans.
If you have any information about Gutierrez's whereabouts, you're urged to contact the Orange County Sheriff's Department at (714) 647-7055 or (714) 628-7170.