Canterbury police are trying to track down a missing 58-year-old man.

They say they're concerned about John Old, who's from Mairehau in Christchurch.

He was reported missing on Thursday afternoon.

Old is described slim, 5 foot 6 inches tall, with short grey hair and a short white beard.

He's believed to have flown into Christchurch Airport a week ago, which was when he last spoke to his family.

He's thought to be in the Canterbury area, possibly in the high country lakes.

Any information on his whereabouts since last Saturday afternoon, or sightings of him, should be reported to 111.