Malcolm Brookes has not been seen in the Llanidloes area of Powys since Monday, when he was spotted in the town centre.
His family are concerned for his welfare and police are appealing for help.
Anyone who has seen Malcolm, or may know of his whereabouts, are urged to contact the police.
Call police on 101.
Alternatively, contact Crimestoppers anonymously on 0800 555111 or at crimestoppers-uk.org