The government is looking at charging international visitors more for national park facilities, such as huts, to help pay for the costs of dealing with the surge in the number of tourists.
Tourism numbers are expected to rise from 3.1 million this year to 4.5 million by 2022.
The amount tourists spend is expected to increase 65 percent, to $16 billion in 2022. International tourists spent $9b in New Zealand last year.
Associate Tourism Minister Paula Bennett is ruling out charging people to walk in the national parks but she has been in talks with Conservation Minister Maggie Barry about raising charges for some facilities.
But she said it was too soon to say whether international visitors would have to pay more than locals.
Mrs Bennett said other user charges for tourists needed exploring but New Zealand did not want to have a reputation for ripping people off.
The figures were released by the Ministry of Business, Innovation and Employment at the annual TRENZ tourism conference in Rotorua today.