A missing 52-year-old man was last seen at the Kingston Railway Station.
Hai Quach was last seen on Friday afternoon, but did not get on a train, ACT police said.
He is described as being of Vietnamese appearance, short, with a slim build and dark balding hair.
Mr Quach was last seen wearing sandals, dark shorts, a light coloured shirt and a dark puffer vest with a white logo on the front, police said.
Police said the man is not believed to have access to a car but does use public transport, including taxis.
"Police hold concerns for his welfare and are requesting the public's assistance in locating him," they said in a statement.
"Anyone who has seen Hai or who may have information regarding his whereabouts is urged to contact ACT Policing on 131 444. Please quote reference number 7538682."