Denbighshire County Council's planning committee approved plans to install the Pepsi Cola Loop ride which used to be a key feature at Rhyl's Ocean Beach before its closure last year.
Directors at the 25 acre site, between Rhyl and Prestatyn, say the new ride is essential to attract more visitors and protect the 50 jobs there. But residents believe the Pepsi Loop will lower the tone of Ffrith Beach and make it difficult to enjoy a peaceful life.
Rachel Garnett, whose home is the nearest to the proposed site, said the new ride was a step too far.
She said: "Ffrith Leisure promised something a lot different to this in their original proposals not a screaming funfair.
"This is a residential area and they're not just breaking promises but breaking clauses in their lease agreement. They told us they would have an ice rink and mini-golf not tatty rides from an old funfair."
One of her neighbours, Jan Szabo, was also concerned about the noise levels.
She said: "The noise levels there aren't too bad at the moment but they have the majorettes on at the weekends and turn the speakers up full blast," said Mrs Szabo. "We wanted to sit in the garden but went out in the end because there's only so much 70s music you can take and when you've heard Ra Ra Rasputin 20 times it's too much.
"They've done a fantastic job with the restaurant and the bowling alley but the fairground doesn't fit in with the high standards of facility they have brought here," she said.
Harry Orenstein, who is a member of the board of directors at Ffrith Leisure, said the business could not survive on local trade alone and they had to do something to attract visitors
He said: "There has always been planning permission on part of the Ffrith Beach for a fun fair which pre-existed our arrival," said Mr Orenstein.
"All the facilities at Ffrith Beach will be kept at a high level of maintenance and safety standards. We are continually monitoring the sound levels on the boundary of the site in line with World Health Organisation guidelines."
He also promised to look at the sound levels caused by the majorettes