Simon Morris, 51, was last seen on Blackpool Old Road, Poulton at around 6pm on Saturday (December 7).
His family haven’t seen or heard from him since, behaviour which they say is "very unusual".
His dad, Barry Morris, said today: “Simon, if you see this appeal then please, please will you get in touch and let us know you are okay.
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"We are worried sick about you and just want you to come home.
"If you are worried about something or upset or struggling then please come back home so we can help you. We miss you son.
“I would also ask any of Simon’s friends who might know where he is or can shed any light on why he might have gone missing to get in touch.
"If anyone has seen him, or thinks they might have any information, just to give us a little glimmer of hope he is safe. We are desperate for news.
“I would encourage anyone reading this to have a good look at Simon’s picture. If you have seen him, or know where he is, please come forward immediately. Thank you.”
Simon is described as white, around 6ft 1ins, of medium build with dark hair and is clean shaven.
He was last seen wearing a dark brown coat, dark pants and black shoes.
Anyone with information is being asked to call 101 quoting log number 587 of December 8.
For immediate sightings please call 999.