Officers have renewed their appeal for the public's help in finding Steven Mead after spending a second day searching for him in the North York Moors National Park.
Steven left his home within the grounds of Arden Hall at Hawnby, near Helmsley, at around 8.40pm on Tuesday.
The 53-year-old was seen to enter the woods surrounding Arden Hall and remains missing.
He is described as white, of medium build with greying, wavy hair.
When he was last seen, Steven was wearing black trousers, a black fleece and walking boots.
Police said he does not have any money, transport or mobile phone with him.
A North Yorkshire Police spokesman said: "Officers, police search dogs and search and rescue volunteers have carried out extensive searches in the area today and officers are now appealing to members of the public to contact the police if they have seen a man matching Steven’s description.
"The area where he has gone missing from is isolated and rural with a number of walking routes that lead across the moors and through woodlands. However, it is possible that Steven may have headed to a more built up area."
Officers are appealing to both walkers in the area and to anyone who believes they have seen Steven in the area between Thirsk, Helmsley and Stokesley to contact them.
Anyone with any information is asked to contact North Yorkshire Police on 101 and pass information to the Force Control Room.