Harry Smith, 16, was last seen by his friends outside the Co-op in Colburn at 10pm yesterday.
It is believed Harry was wearing a black Jack Jones hoody, dark coloured bottoms and dark coloured Nike trainers.
A spokesperson for North Yorkshire Police said: "Officers are becoming increasingly concerned for Harry’s welfare and are appealing for anyone who has seen him, or who has any information about his whereabouts, to get in touch."
Call police on 101, press 1 and pass information onto the force control room.
Quote reference number 12170176370 when passing on any information.