A convicted sex offender won his legal challenge to have the site taken down.
High Court judge Mr Justice McCloskey found that the man, whose identity cannot be revealed, had his human rights breached. The judge has given Facebook 72 hours to take the page down.
A spokeswoman for Facebook said: "We are considering our next steps in light of the court judgment and we have nothing further to add at this stage."
The man, known only as XY, started legal proceedings against the social networking site after discovering his photograph and threatening comments were posted on the page.
More than 5,000 people have liked the page entitled 'Keeping our kids safe from predators'.
Some of the latest posts were written after Lord Justice McCloskey made his ruling.
One read: "Can facebook not step in here and fight this battle 4 us..... what the point of having a social netwok (sic) if we can post facts on people especially wen its 2 keep our kids safe....... Come on Mark Zuckerberg we need your help..... plz plz plz....."
Another wrote: "Let down a bag full :( no justice at all......Not only me but every victim of sex abuse every kid in the land....... This is what we get for trying 2 protect our kids."
Facebook is understood to have removed the man's photo and comments made about him but his legal team insisted that the page should be shut down.