Watch a report above by ITV News Anglia's Russell Hookey.
Traders at Cambridge Central Market claim a proposed rise in pitch rents will hit them hard.
The City Council wants many stallholders to pay 2.5 % more.
It says the increase will pay for improved facilities and has offered a reduction on Monday and Tuesdays.
But some businesses say it's come at the wrong time.
The City Council is due to look at updating the Charter Market Regulations which govern how the general and Sunday market operates.
It comes after a consultation with traders towards the end of 2017 and as well as changes to fees, it includes the following:
- To help make Cambridge greener, by requiring hot food and drink traders to use non-plastic, recyclable materials for their containers.
- To decrease the risk of fire and lessen fumes, by requiring hot food traders to use flame retardant sheeting.
- To encourage traders to turn up to trade and avoid 'no shows', by charging casual traders when they confirm they wish to have a pitch, rather than after they have used it.
Monday and Tuesday trading could be reduced by a third to make them more attractive to traders.
All premium pitches on the more popular trading days, Wednesday to Sunday, could be increased by 2.5%.