Sussex Police is extremely concerned for the welfare of Martin Henderson.
Martin, 52, was last seen around 12.20pm on Sunday (7 March) in the Luxford Lane area of East Grinstead.
He is described as 5' 5", of small build, bald, clean shaven and with blue eyes. Martin was last seen wearing beige combat trousers with pockets on the side, a dark top, walking boots and carrying a large rucksack.
Investigating officer PC Carly Churchill-Wright said:” We are urging everyone who is out and about in the area to keep a look out for Martin.
“This is unusual behaviour from Martin and we are really concerned for his welfare.
“Anyone who sees Martin should dial 999 immediately.”
If you have any other information which could assist our investigation please report online or call 101 quoting reference 451 0f 07/03.