Police hope the Israeli man missing in the Buckland Peaks area, near Westport has military training.
A search and rescue operation is under way after the 49-year-old went missing on Tuesday.
He's believed to have entered the Paparoa National Park at 10am, wearing dark trousers and a red jacket.
Senior Constable Mike Tinnelly says police have concerns for his safety.
He says the weather's cold, but they're hoping, as with many Israeli citizens, he's got some military training behind him.
