Mark Ribbons has been missing since Saturday. Credit:WA Police

Police are calling on the public's help to find a missing 46 year old man last seen at Graylands Hospital, Mount Claremont 3pm Saturday.

Mark Bradley Ribbons is described as fair skinned, approximately 170cms tall, with a slim build, short brown hair and brown eyes.

Police hold concerns for his welfare said anyone who sees him should not approach him but call them immediately on 131 444.