The 27-year-old was last seen earlier this morning near Beckenham.
Cannington Police need the public's help to locate Mr Matthews as they hold concerns for his safety and welfare.
The 27-year-old was last seen around 4.20am this morning in Beckenham.
He is described as 170cm tall, with fair skin and of medium build.
Mr Matthews may be driving a 2016 silver Peugeot Station Sedan, registration number 1GEV 941.
Anyone who sees the man or his vehicle, or who has information regarding his whereabouts, is asked to call Police on 131 444.