The price of annual parks passes will be reduced from $96 to $90 from May 1 next year, while day passes will be increased from $12 to $20.

The government expects the changes to generate additional revenues of about $3 million per annum, which it says will all be reinvested into "infrastructure, maintenance and services" across parks.

But Tasmanian National Parks Association president Nicholas Sawyer said he'd believe it when he saw it.

"It's a good sign that the money's going straight back into the parks budget, not just consolidated revenue," he said.

"Our big concern is that an awful lot of the expenditure and staff time in parks is going on providing facilities for front country tourists.

"There's still a big backlog of long-term maintenance and work that needs to be done for environmental protection that's increasingly being overlooked in favour of spending money on tourism infrastructure."

Mr Sawyer said boardwalks in the Southwest National Park, such as in the Eastern Arthurs Range, had deteriorated over the years and had been further damaged by the recent bushfires.

Tasmanian Walking Company general manager Heath Garratt, for whom about 97 per cent of his customers come from outside Tasmania, said the first thing the increased revenue should be spent on was track upgrades in the state's national parks.