Social media is driving tourists to to set off on hikes they are not prepared for, says Department of Conservation (DOC) visitor risk advisor Don Bogie.
"All those really neat photos don't really show you the hazards," Mr Bogie said.
Visitors needed to wear suitable footwear and consider if they had the right skills to walk in challenging environments, he said.
"The New Zealand weather is really unforgiving.
"If you get caught out without the right clothing or equipment, things can go from a nice day to a really unpleasant and then a really dangerous one really fast."
DOC and police have called for New Zealanders to help inform tourists of the risks, after an Indian tourist died while hiking on the Tongariro Crossing earlier this month. It was the second tourist death in the area within weeks.
The New Zealand Mountain Safety Council reported 57 trampers lost their lives in the 10 years to June 2017, with international tourists accounting for nearly half of those deaths.
More than 3600 trampers were involved in search and rescue operations during the same period.
Mr Bogie said individuals were responsible for keeping themselves safe outdoors - not DOC.
The department encourages outdoor safety by providing information, building huts and placing signs and markers on tracks.
More than 600,000 international tourists head out on hikes of at least three hours in New Zealand every year - and that figure is set to grow.
Hong Kong tourist Cherry Kwan has been exploring New Zealand's outdoors, visiting Franz Josef Glacier and Queenstown.
She researched before arriving, but said tourists who didn't speak much English might struggle to stay informed or understand outdoor risks.
"It's okay for me because my English is ok... but if others can't speak very well in English, maybe it's a bit difficult for them," Ms Kwan said.
Tourism Industry Aotearoa advocacy manager Steve Hanrahan said communities needed to play a strong role in visitor safety.
Visitors should consider hiring a guide for alpine tramps, he said.
Tourism Industry Aotearoa manages tourist safety website supportadventure.co.nz.
It has four main pieces of advice for trampers - stay in a group, keep an eye on the weather, be prepared to turn back, and take sufficient supplies.