A complaint has been lodged with the police over the planned Boobs on Bikes parade in Auckland.

The parade, which features bare-chested women on motorcycles parading down Queen Street, is scheduled for Wednesday as part of the Erotica Expo.

Conservative lobby group Family First have lodged the complaint.

Spokesman Bob McCoskrie says he's written a letter to the Auckland Police Area Commander and the Minister of Police asking them to prevent the stunt going ahead.

"We believe it's shocking that an offensive parade, which is basically promoting the pornography industry is allowed to go down a main street in Auckland during school holidays."

"There'll be lots of families, lots of kids, and it will be highly offensive."

"We're calling on police and the council to stop this parade going ahead. This is not a Santa parade or a sports event or a celebration. This is a marketing ploy for the porn industry."

Auckland Feminist Action Co-Coordinator Meg Rayner believes that while sometimes there are good reasons a woman might show her breasts in public, Erotica is possibly not one of them.

"It's done in a context where women are being objectified in a misogynistic way for the enjoyment of mostly men. There are all kinds of problems with that. Women shouldn't be viewed just for the enjoyment of certain other people."

Auckland Council has not received an event permit application for the annual Boobs on Bikes parade, but will monitor the event.

Community Arts and Culture general manager Graham Bodman said they will be advising organisers of the consequences should any laws be breached.