Hayden Cranch is missing from his home in Heathfield and there are concerns for his welfare.
Hayden, 32, was last seen at home at around 3pm on Monday (July 30), but it is thought that he may be in Brighton.
He is white with a south European complexion, 6ft 1in tall, of broad build, with short cropped black hair. He was wearing a black hooded top and black tracksuit.
He is likely to become worried if approached, police say, so if you see him please dial 999 quoting serial 390 of 31/07. If you know of his whereabouts, please report online at https://sussex.police.uk/appealresponse or call 101.