David Lord, from Lancaster, has been missing for four days.
The 59 year old was last seen on West Road in Lancaster at 7:30am on Saturday.
Police said they are concerned for him, and said he has links to Blackpool.
When he disappeared, David was wearing a blue T-shirt and beige trousers.
He has mousey grey hair, a beard, and glasses.
Anyone who sees David can contact police on 101.