Aryana Vatani was last seen on Monday in the 4000 block of Sherry Mist Lane, deputies said.
Vatani is described as 5 feet 1 inch tall, 150 pounds, with brown eyes and brown/red hair. She was wearing black leggings, a black shirt and a green jacket.
Anyone with information is asked to call the Harris County Sheriff's Office Missing Persons Unit at (713) 755-7427.