A search is underway in the Western Australian Wheatbelt town of Wagin for an 87-year-old man with dementia who has not been seen since he went for a walk on Saturday morning.

James Ballantyne was last seen on Leonora Street (also spelled Leonara) in Wagin at about 10.30am on Saturday, according to police. The town is an agricultural centre about 225km southeast of Perth.

WA Police said on Sunday that Ballantyne lives with dementia and may be unable to find his way home. Police believe he may have sought shelter in the area overnight, and are urging residents to check their backyards, sheds and vehicles as part of the search.

"Police are urging residents in the area to check their backyards, sheds and vehicles," police said in a statement, as reported by 7NEWS Australia.

Ballantyne is described as being 183cm tall, of medium build, with short greying hair. He was last seen wearing a navy-blue jumper and khaki-tan pants (also described as a navy blue jumper and khaki pants).

The search is being assisted by WA Police Air Wing assets and drone operators, with SES personnel also joining the effort, according to PerthNow. A police spokeswoman said the search involves police aircraft and SES personnel.

Authorities have asked anyone who sights Ballantyne or has information about his location to contact police immediately on 131 444 or Crime Stoppers.

Public assistance sought

Police have stressed the importance of public assistance in locating Ballantyne, particularly given the risk that his dementia could leave him unable to find his way home. Residents in the area have been asked to check their properties, including backyards, sheds and vehicles, in case he sought shelter overnight.

The search operation involves a coordinated response, with police aircraft, drone operators and SES personnel taking part. The deployment of these resources reflects the urgency of the situation, as described by PerthNow.

Ballantyne's family and authorities are appealing for any information that could help locate him.

Anyone with information is encouraged to contact police on 131 444 or Crime Stoppers.