Joao Nobrega was last seen at around 10.30am on Sunday (April 3), when he left his home address in Stone Crescent to go on a regular daily walk.
His family and the police are growing increasingly concerned for his well-being as he has not been seen since.
Mr Nobrega who wears glasses is Portuguese and speaks very little English.
When he left the house on Sunday he was wearing blue jeans, a brown suede jacket and a black bobble hat.
He has been described as white, 5ft 9ins tall, of medium build with greying short hair.
Police in Ealing also appealing for help to trace a teenage boy from Ealing who has been missing since March 26.
Anyone with information on Joao’s whereabouts is asked to call Hounslow police via 101 quoting reference number 16MIS013556.