The Devon Partnership Trust made more than £10,000 in car parking charges in 2023-24, new figures show.
Figures from NHS England reveal Devon Partnership NHS Trust earned £25,000 in car parking fees in the year to March.
All of this was for visitors and patients, with the trust not taking any fees from staff.
The data shows the trust also spent £14,000 on parking services over the same period, meaning in total it made £12,000 from parking.
Across England, NHS trusts made a net revenue of £165.6m from parking charges. This was from a total of £242.8m in car parking fees, after spending £77.2m to run parking services.
Despite the Devon Partnership Trust not taking any revenue from its staff, NHS workers across England paid £70.5m in parking fees.
GMB, a union which represents thousands of NHS staff, said charging staff to park at work was "kicking them while they are down".
The union's national secretary, Rachel Harrison, said NHS workers have suffered "rocketing workloads, chronic understaffing and the fallout from a global pandemic".
She said: "Health workers are on their knees – they need help and support. Charging them to park is kicking them while they are down."
The GMB is calling on the Government and NHS employers to scrap staff car parking charges.
The figures also show there were 816 available parking spaces across the Devon Partnership Trust.
Patricia Marquis, executive director for England of the Royal College of Nurses, said: "Nursing staff provide a vital public service and often work unsocial hours and in places where public transport is not always possible.
"They shouldn’t be forced to spend a significant portion of their wages just to park at work."
She added all staff should be able to access "safe, sustainable and affordable" transport, and urged employers and local authorities to work together on the issue.
NHS England said revenue from parking is put towards other services provided by trusts.
A Department of Health and Social Care spokesperson said: "Hospital car park charges are the responsibility of individual NHS trusts, however any charges must be reasonable and in line with the local area.
"Free parking is available for all NHS staff who work overnight."