Facebook has apologised for featuring a dating advertisement using the photo of a teenager who committed suicide after falling victim to cyber-bullying.

The social media company said on Wednesday that it has banned the advertiser that used photographs of 17-year-old Rehtaeh Parsons, from Halifax, Canada, who took her own life after months of cyber-bullying and an alleged sexual assault.

The abuse started after a photo circulated on the Internet showing her alleged rape by four boys.

A Facebook user noticed the ad, and posted screen grabs to Twitter, provoking immediate outrage and a quick response from Facebook.

"This is an extremely unfortunate example of an advertiser scraping an image from the Internet and using it in their ad campaign," a spokeswoman for Facebook said in an email.

She said the ad was removed as soon as it came to their attention, and the advertiser's account was permanently deleted.

"This is a gross violation of our ad policies," the spokeswoman said. "We apologise for any harm this has caused."

The ad was for the online dating site ionechat.com, which placed the photo of Parsons next to text that read "Meet Canadian girls and women for friendship, dating or relationships. Sign up now!"

Parsons' father, Glen Canning, condemned the ad.

"I am completely bewildered and disgusted by this. This is my daughter, Rehtaeh. They have her in an ad for meeting singles. I don't even know what to say," Canning wrote in his blog.

The website for ionechat was not available for comment on Wednesday.