Police would like to hear from anyone who may have given a missing Donnybrook woman a lift from Glen Mervyn Dam on Monday evening.

Gail Rose Grenfell was camping with family at the dam until she left about 2pm on Monday and her family and the police are concerned about her welfare.

It is believed she may have made her way to Bunbury and may still be in the Bunbury or Australind area.

Ms Grenfell has a fair complexion, medium height and black hair and was last seen wearing black jeans, a blue tank top and a silver necklace.

She may be carrying plastic bags with more clothes.