A councillor said she has been denied free parking that would save her walking half a mile in her high heels for meetings with the public.
Maxine Smith owns beauty salons in Invergordon and Fort William
Maxine Smith visits the Cromarty Firth Port Authority (CFPA) in Invergordon, Ross-shire, two to three times a week.
She said she has been told she must pay £50 for year-round access to a car park within the site, or walk from parking outside the base.
CFPA said it was a secure area and Ms Smith could obtain a visitor's pass.
The SNP member of Highland Council's Independent/Nationalist administration said her complaint had implications for the local economy.
She said: "When you go into the base it is half a mile from the car park on the outside and, obviously as I am working, I am wearing a pencil skirt, jacket and heels."
Ms Smith, who owns beauty salons in Invergordon and Fort William, said she was not prepared to ask the council to foot the bill for parking.
She added: "The £50 is charged to all clients - even project managers bringing in rigs for work worth millions of pounds are charged for a pass."
In a statement, port manager Captain Ken Gray said the car park within the site must be carefully controlled.
He said: "We are required through law to monitor vehicles entering and leaving the port and it is good practice that we keep the number of vehicles inside the secure area to a minimum.
"CFPA has no objections to Councillor Smith, or anyone else, attending meetings on the service base during working hours.
"Should she wish to take her car into the secure area to visit her constituents, she can obtain a visitor's pass from the security gate.
"Visitors are also welcome to use the external car park, which is only a short distance on foot from the base."
The Cromarty Firth is a deep water port and it and the firth are visited by cruise ships and used for the storage and refurbishment of oil and gas platforms.
Up to 50 cruises have visited Invergordon in a year, bringing with them almost 40,000 tourists.