A new medical plane will boost the Royal Flying Doctor Service in the northern area of Western Australia as part of $23 million in state government funding.

The Royal Flying Doctor Service has been given a boost in Western Australia with a new aircraft that will impact "patient care and clinical outcomes" across the state's northern regions.

The new Pilates PC12 brings the fleet up to 16 and will be the second plane to be based in Broome.

It is part of a $23 million state goverment investment which has also bought two replacement aircraft and funded the Broome RFDS base.

The aircraft was unveiled on Monday at the RFDS base in Jandakot, Perth, and will be fitted out as a flying intensive care unit over the next six weeks.

CEO Grahame Marshall said the service has treated around 9000 people across the state in the last 12 months.

"This aircraft is sorely needed in the north of the state where people are the furthest from medical care," Mr Marshall said.

He added the RFDS has an increasing reliance on public donations, especially after the loss of $6 million funding from the Federal Government.

Nationals Leader Brendon Grylls says the new plane is of "great comfort" to people living in the north of the state.

"As a person living in the country with three young kids who spend a lot of their time trying to hurt themselves it's really heartening to know we have some of the best aeromedical facilities in the world," Mr Grylls said.

Health Minister John Day says the new plane will improve patient care and clinical outcomes for people living, working and travelling in the Kimberley and the Pilbara.

"The service provides a critical lifeline for remote and regional communities and to visitors to popular tourist destinations," Mr Day said.