A man cutting wood found the remains off Tea Tree Road in Bindoon, north of Perth, on Sunday afternoon.
Police are working to identify the deceased person, but say the death is not being treated as suspicious and a report will be prepared for the coroner.
Mary Ann Nix, 69, was last seen on April 1 last year in Bassendean, where she visited the post office.
A neighbour reported her missing after noticing her dogs, which lived with Ms Nix at her home in Lockridge, did not seem to be being cared for.
Ten days later, her car, which was a distinctive burnt orange colour, was found abandoned near Bindoon.
Police said at the time that they were concerned Ms Nix might have been confused or disoriented. She lived alone and had minimal contact with friends or family.
An extensive search for Ms Nix was called off a couple of weeks later. Her family has been made aware of the discovery.
Bindoon is about 80km north of Perth.
– with AAP