Andrew McGibbon was last seen at around 6.40am on Wednesday, January 3 leaving his home address near Airdrie town centre.
Police say it is out of character for the 52-year-old to be out of touch with his family and colleagues and say there is increasing concern for him.
Anyone who has any information on Andrews whereabouts is being urged to contact police.
Sergeant Pamela McGillivray said: “It is out of character for Andrew not to be in contact with his family and work colleagues, and they are becoming increasingly concerned for his welfare.
“Our enquiries are ongoing, and I am appealing to anyone who has seen Andrew since this time or who has any information on his whereabouts to get in touch.”
Anyone with information is asked to contact police via 101, quoting incident number 1392 of Thursday, January 4.
Andrew is described as being white and 5ft 6in tall with a slim build, balding/ short grey hair and a goatee.
He was last seen wearing a black beanie, Gym King jacket, jeans and shoes.
He was carrying a black backpack with white markings and a large black holdall.
