A PERTH woman will need facial surgery after allegedly receiving serious injuries from being kicked in the face by a teenager.

The woman in her 30s cycled past a group of teens along Twickenham Dr in Kingsley at about 1.50am on Saturday, October 26 when one group member knocked her off her bike.

She was kicked in the face as she was laying on the ground, causing serious facial injuries.

The offender, described to be aged 15 to 17 years and 162cm tall with a medium build, also demanded money before the group walked away.

The group consisted of males and females aged 15 to 20 years.

WA police urge anyone with information to call Crime Stoppers on 1800 333 000 or report online at www.crimestopperswa.com.au.