Restaurant chain Coppa Club wants to bring a pavilion to The Lanes.
The Berkshire and London-based chain has put forward plans to build the curved structure in Brighton Square, incorporating the dolphin sculpture which sits at its centre.
Its design is similar to the Paradise Pods at Coppa’s Tower Bridge venue.
Supporters sent 138 letters backing the scheme, highlighting the need for improvements in the area and how the restaurant would generate jobs.
Stuart Stanley, a trader in Meeting House Lane, Brighton, said: “The constant stream of temporary tenants means that the square has a really run-down feel and I often hear members of the public commenting on this.
“This proposed development to the square can only be a massive improvement.”
Mark Hawkins, of The Lanes Armoury, in Meeting House Lane, said: “Visitors today want to see shopping centres revitalised and repositioned through great facilities.
“They want to see schemes working hard to deliver value but also act as a catalyst for wider regeneration.
“Coppa Club, in this location, is just what is needed to revitalise this specific area that has somewhat declined over the past two decades.”
Letters in support of the project have come from as far away as Cornwall.
But 34 letters opposing the project say that the building is not suitable and that public space should not be used by private enterprise.
Graham Hale, of Preston Park Avenue, Brighton, said: “The dolphin fountain in the centre is by the sculptor James Osborne who was born in Brighton and spent his childhood here.
“Brighton Square became the home of his largest public fountain depicting his own children astride two life-size dolphins.
“This should not be messed about with and isolated from the public.”
Jane Tuckwell, of Brunwick Road, Hove, said: “I object to the ownership of a public space and fountain which should be enjoyed by all.”
Planning officers are advising councillors to reject the application on the grounds it would take up public open space and restrict people’s movement across the square.
Brighton and Hove City Council’s planning committee is due to discuss the plans at a meeting at Hove Town Hall on Wednesday (June 6).
Sarah Booker-Lewis is the Local Democracy Reporter for Brighton & Hove.