Gary Butt, 73, who lives with dementia, left his home in the Ballarat suburb of Golden Point at about 9am on Sunday, September 22, and failed to return home.
He was reported missing to police later that day and inquiries revealed Gary was last seen near Shepparton railway station at 10pm that same day.
Police said Gary had no known ties to the Shepparton area, so it was not known why he was there.
Gary does not have a mobile phone and left with limited food and clothing and without his medication.
Police have spoken to family, friends and neighbours, conducted an extensive canvass for CCTV and exhausted other inquiries in a bid to find Gary, to no avail.
On Wednesday, a large contingent of police from Ballarat and Shepparton, Search and Rescue specialists, as well as more than 50 SES volunteers, will conduct a search along the Midland Hwy in Shepparton East.
The ground search will cover farmland, orchards, irrigation channels and grassland adjacent to the highway.
Residents and business owners along the Midland Hwy are asked to check their farm sheds and other structures for Gary.
While the search is under way, police are keen to renew their appeal to the community for help to find Gary and have re-released CCTV images and footage of the last time he was seen at Shepparton railway station.
Gary is described as having a slim build, long grey hair and a white beard, and he usually wears a black beanie.
He was last seen wearing a long black jacket, a black beanie, brown and white chequered flannel shirt, light-coloured pants and dark-coloured shoes.
Police said Gary may be carrying a green shopping bag of clothing.
Anyone who sees Gary is urged to call 000, or if you have information about his whereabouts, contact Crime Stoppers on 1800 333 000 or crimestoppersvic.com.au
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