A trip by city leaders to Cannes has been dubbed a jolly by a campaign group.
The TaxPayers Alliance has criticised the visit by a team of six to showcase stalled plans to redevelop Sheffield city centre.
Lib Dems have also criticised the make-up of the delegation.
Sheffield City Region is sending a team of six - including Coun Leigh Bramall and chief executive John Mothersole - to the annual MIPIM conference at the swanky five-star Carlton Hotel.
Representatives from Sheffield could find themselves rubbing shoulders with London Mayor Boris Johnson, this year’s guest speaker.
Bloggers at last year’s event on the Riviera described long lunches, champagne and canapes.
But Jonathan Isaby, chief executive of the TaxPayers’ Alliance, said: “This conference is little more than a fancy taxpayer-funded get-together for council officers and companies. Many residents will wonder what they get from paying to send local politicians on a jolly to Cannes.”
Lib Dem Coun David Baker said: “Sheffield has been represented at this particular exhibition before but when Lib Dems ran the council we didn’t think it was appropriate to send a councillor.”
The council has defended the need for the trip to attract investment for its city centre redevelopment plan, formerly Sevenstone.
A spokeswoman said costs had been kept to a minimum and representatives will not be guests of the Carlton on the visit. They will instead stay in nearby Antibes at a cost of £71 a night.
Coun Bramall said: “We are there to sell Sheffield on the international stage and attract investment to be ploughed in to the city - simple as that.”