Ben Ludlow is last known to have been in the Swanscombe area at around 6.30pm on Monday 17 May 2021.
The 21-year-old is described as being around six feet tall, of medium and with brown hair that is short at the sides and longer on top.
When he was last seen, Ben was wearing light blue jeans and a grey jumper.
Inspector Paul Stoner said: ‘We are very concerned for Ben’s welfare and are urging anybody who sees him or knows where he might be to contact us.’
Anyone with information is asked to call Kent Police on 999 quoting 17-1260.