National is promising a "bold" new electric car policy. It says one in three cars in the government fleet of 15,500 cars will be electric or electric-hybrid by 2021.
The target was announced by National's Transport spokesperson Simon Bridges and Climate Change Issues spokesperson Paula Bennett on Saturday.
"A new National government will use the buying power of government to achieve the target and increase the number of electric vehicles in New Zealand," Mr Bridges says.
Since May 2016, the number of electric vehicles registered in New Zealand has grown from about 1,300 to more than 4,200.
The government already has a target of having 64,000 electric vehicles in New Zealand by 2021.
"We want the public sector to lead by example," Mrs Bennett said.
"National knows that electric vehicles are the future. A move from petrol and diesel to low emission transport is a natural evolution, and it is our aim to encourage that switch sooner, rather than later."
More than 85 percent of the country's electricity is generated from renewable sources, and a fully electric vehicle has 80 percent less emissions than a petrol vehicle.
Transport makes up around 17 percent of New Zealand's emissions.