Traders have formed a group to oppose plans for a new £4 million public square in the city centre.
Workers in and around St Nicholas Place said the development of Jubilee Square, which would replace the car park and park-and-ride bus terminal in the area, will have a negative impact on businesses.
City mayor Sir Peter Soulsby is hoping to create a plaza for families, with an area to hold markets and festivals.
Traders against the move have now formed an opposition group and said they would be sending letters to the city council objecting to the plans.
They also hope to organise a meeting with council representatives before the proposals are considered by planning bosses in April.
Group spokesman Steve Cooper, of Abel Alarms, said changes to the road network and the loss of parking spaces would not be good for business.
"A large number of businesses are very concerned about what is being proposed," he said.
"We are concerned changes to the traffic access, including a ban of left turns from Vaughan Way into the High Street, will impact on businesses."
Pam Kooner, owner of Memsaab Restaurant, in High Cross Street, said: "Our business will suffer if the plans are implemented. They want to remove car parking our customers use.
"They also want to make it two-way in High Cross Street and that will prevent taxis dropping off customers in the parking bays, which will be removed.
"That will hit our footfall and our business will be affected. We feel that we have not been properly consulted."
Steve Pateman, who runs private hire firm Circle Taxis nearby, said he would be hit badly by the removal of 47 car parking spaces.
"Nobody seems to be listening to the businesses in the area," he said. "If they remove our parking it will prevent us meeting the needs of our customers because our drivers will have drive to our offices to pick up fares. At present, we can respond immediately if someone steps in the office and wants to catch a train."
Aatin Anadkat, director of Maiyango Hotel, said: "We need to embrace change and try to encourage more visitors on the back of the Richard III discovery.
"I am in favour of improving Leicester. However, I have concerns about the policing of the new plaza at night. We do not want it to become a place for vagrants."
Sir Peter has repeatedly said he intends to find replacement parking in the vicinity, but no provision has been included in the plans submitted to city council planning officers.
He said: "The development of the plans for Jubilee Square involved extensive consultation with businesses in the area, many of which I have met with personally.
"I have listened carefully to their concerns and recognise how important it is to ensure traders have all the access they need and that businesses are not disrupted.
"Jubilee Square will help transform this area of the city centre."
Anyone wishing to comment on the scheme should do so by contacting the council before Tuesday.
