Tuan Huu Dinh, who was in a tour party from Vietnam, was last seen leaving the Macdonald Cardrona Hotel near Peebles on Saturday just after 20:30.
The 32-year-old, who police said had "limited English", has not been heard from since.
He is described as being of south east Asian appearance, 5ft 6in, wearing a black jacket, jeans and Nike trainers.
Insp Kevin Harris said: "Local officers have been conducting inquiries within the Peebles area to trace Tuan since he was reported missing.
"We are keen to establish his whereabouts as soon as possible and anyone who believes they have seen him since last night is asked to come forward.
"In addition, we would ask Tuan to get in touch with friends, family or police and let us know you are safe and well."
Police are asking for the public's help to find a tourist missing in the Scottish Borders.