Police are asking for the public's help to find a 1995 white Ford Falcon sedan last seen on Wednesday in Gidgegannup and Middle Swan.
Police have concerns for the welfare of the occupants, believed to be a man and a child.
The Ford has a registration plate reading KO 8536.
The man is in his 40s, with fair skin and several tattoos.
It is believed a child may also be in the vehicle.
The sedan was seen at the intersection of Toodyay Road and Old Toodyay Road in Gidgegannup on Wednesday.
It was also sighted leaving a gravel car park before heading west on Toodyay Road towards Red Hill.
It was last seen near Campersic Road, Middle Swan.
Anyone who knows where the Ford is or has information regarding its whereabouts is asked to call police on 131 444.