Cornelius Van Der Wetering, 54, was last seen in the Tomich area, about 30 miles from Inverness, on Wednesday December 28.
He had been staying at a guest house in Inverness and it is thought he had planned a walk to Kyle of Lochalsh through Glen Affric, a distance of more than 70 miles.
Officers are appealing to any walkers, guest house owners, bus or taxi companies in the area to contact police if they have been seen him.
Mr Van Der Wetering is described as tall, slim and with short grey hair. He was wearing outdoor clothing and carrying a large rucksack when last seen.
A Police Scotland spokesman said: “Mr Van Der Wetering was last seen in the Tomich area on December 28, having previously stayed in guest house accommodation in Inverness.
“It is understood he planned to walk from Tomich towards Kyle of Lochalsh via Glen Affric.
“Officers are appealing to anyone who may have seen a man of his description walking in the Tomich/Glen Affric or Lochalsh areas since December 28 to make contact via 101.”
Mountain rescue teams have already carried out a number of high-profile searches for people who failed to return from hikes so far this year.
Robert and Cathy Elmer, from Leicestershire, and their dog were found in the Cairngorms on Monday after they were forced to take shelter overnight in a bivvy bag as bad weather closed in during their New Year’s Day walk.
On Tuesday, two young mountaineers carried a hypothermic walker to safety after he got into difficulty on Ben Macdui - Scotland’s second-highest peak.
Rescue teams have urged people to check detailed weather forecasts and carry all necessary equipment before setting out over the winter.