A teenager with a rare blood disorder is leading a push to cap parking fees across NSW hospitals.

Gidon Goodman, 13, requires regular medical infusions to control his symptoms and has started an online petition for parking rates to be independently regulated.

The change.org petition has so far received more than 46,000 signatures.

The teenager said he was worried people would stop visiting sick family members in hospital because of high parking costs.

"It's a disincentive to visit someone, which is horrific because people who visit sick people are actually, in my opinion, some of the greatest people in society," he said.

"They should be rewarded for visiting sick people, not slapped with a parking fee."

A regulating agency, such as the Independent Pricing and Regulatory Tribunary, should be charged with setting capped rates at hospitals, he said.

He said while his family was able to afford the parking fee, it was prohibitive for people on low incomes.

"There are people who actually are spending more on hospital parking than their medication and if you're not lucky like we are, it can be a lot, figures like $10,000," the boy said.

"That can be a third of your income for a year."

Health Minister Jillian Skinner's office said the Government was committed to providing affordable car parking for patients, loved ones and staff at public hospitals.

Individuals should speak to hospital: Government

"Individuals with special needs or challenges should contact their hospital to discuss what parking options and further concessional rates may be available to them," a spokeswoman for Ms Skinner said.

A NSW Health spokeswoman told the ABC it received $38.7 million in revenue from parking fees in the past financial year.

She said each Local Health District was responsible for setting car parking fees at existing public hospital car parks, except for those under long-term private contracts.

"It is at the discretion of each local health district as to how they allocate the revenue from car parking in public hospitals," the NSW Health spokeswoman said.

"Each district is responsible for the management of their annual budget and directs funds to goods and services, or infrastructure improvements, in accordance with their respective priorities."