Police are seeking public assistance to locate 17-year-old Crystal Walker, who has been reported missing from the Lismore area.

Crystal was last seen in Goonellabah last Tuesday, 7 January.

After efforts to locate her were unsuccessful, her disappearance was reported to Richmond Police District who commenced inquiries.

Concerns are held for Crystal's welfare due to her several health issues.

She is described as being of Aboriginal or Torres Strait Islander appearance, approximately 170cm tall, of a medium build, with short dark hair and brown eyes.

Crystal is known to frequent areas including Goonellabah, Ballina, Lismore and Alstonville.

Recent reports suggest she may be in the Ballina area.

Members of the public with information regarding Crystal's whereabouts are urged to contact Lismore Police Station or Crime Stoppers on 1800 333 000, or via the crime stoppers website.

Information will be treated confidentially.