A female teenager has died after she was hit by a car on Kwinana Freeway in the early hours of Sunday morning.

A police spokewoman said the 19-year-old pedestrian was hit about 4.30am when she was walking in the southbound lane of the freeway near Russell Road in Atwell.

The teenager attempted to cross the freeway but was struck by a blue Kia Rio that was travelling southbound.

The 19-year-old woman from Parmelia died at the scene.

The freeway was closed for several hours.

Major Crash investigators are seeking witnesses who may have seen the Kia Rio driving in the area prior to the crash, saw the crash or may have dash camera footage, to call Crime Stoppers on 1800 333 000 or report online at crimestopperswa.com.au.

More to come.