The item will be posted on eBay by event agency Chillisauce.co.uk on October 18 from 6pm.
The agency's director Adrian Simpson said: "This is a once-in-a-lifetime opportunity to own a landmark piece of underwear and all for a good cause.
"Our aim in auctioning the bra is to build awareness and involvement in 'Wear It Pink Day' as well as raise money for Breast Cancer Campaign in the process."
Chillisauce.co.uk aims to raise £1,000.
'Wear It Pink Day' takes place on October 28.
> Businessman selling life on eBay for £2.2 million
> High school put up for auction on eBay