There are welfare concerns for Thomas 'Eddie' Power, who was last seen at Fiona Stanley Hospital where he was receiving medical treatment.
The 65-year-old resides in North Lake but is known to frequent the Mandurah area.
He is described as 170cm tall with a slim build, green eyes, light brown hair and has several tattoos on both forearms.
Police believe he is travelling on foot and it is not known what clothing he was wearing when he disappeared November 5.
Anyone with information is urged to contact Police on 131 444 and reference IR 131120 1000 16896.
Baldivis Sports Complex officially complete with unveiling of final stage
Teen dies at Logue Brook Dam
Mandurah named WA’s Most Accessible Community
Police attend separate crashes in Lakelands and Port Kennedy
Fresh new look for Roger May Machinery Museum
Tragic end to search of missing FIFO worker
Accused arsonist charged over Bertram fires
Bondi Beach Statement
Police issue 31,000 driving infringements in first month of new AI cameras