Martin Rhodes, 46, was reported missing on Wednesday (1 May) evening, having last been seen that morning.
Mr Rhodes from West Yorkshire is understood to have planned to go walking locally and searches have been ongoing in Kinlochewe.
Dundonnell Mountain Rescue Team, Torridon Mountain Rescue Team, RAF mountain rescue and HM Coastguard R151 are involved in the search.
Emergency services are appealing to walkers planning on visiting the area to keep an eye out for the missing man. Police have not yet released an image of Mr Rhodes.
Mr Rhodes is described as being 5ft 4in tall and of slight build with short brown hair.
It is not known what he was wearing but he is known to have been carrying a black rucksack.
Inspector Jamie Wilson of the Highland and Islands police division said: "We are growing increasingly concerned about Martin's wellbeing due to the passage of time since he was last seen.
"We would urge anyone with information which could help locate him to come forward as soon as possible.
"Martin is an experienced hillwalker and is familiar with the area.
"We working to establish what route he may have taken and so would urge anyone who believes they have seen him at any time since 8.30am on Wednesday to come forward.
"Anyone with information can contact police by calling 101, quoting incident 4582 of May 1."