Staff at Walsall's Manor Hospital have staged a demonstration about the rising cost of car parking in its grounds and a lack of available spaces.
Nurses, porters and healthcare workers say it is taking up to an hour to find a space and protested on Wednesday.
Union Unison said since January parking fees have risen by 300% for staff and more than doubled for patients.
Hospital managers say the new system is making it easier for patients and there are plans to extend the staff car park.
The union said staff used to pay £26 per year to park anywhere on the site.
'Worked with staff'
They now have to pay £60 to park in the outer circle and £120 to park in the inner circle.
Visitors have had there charges increased from £2 per day, to £5 per day.
Sue James, chief executive of the hospital said she was aware of teething problems while the parking arrangements were changed.
"I regret that staff have been inconvenienced, but I hope that the worst of the problems will soon be over," she said.
"We have worked closely with staff in the planning and implementation of these new arrangements and, as a result of the discussions we have had, we have reduced the planned charges, installed much improved security and extended the staff car park."