A VICTIM of child sex abuse has found herself in court after upsetting her abuser with a Facebook post that outed him as a predator.

The Warwick Magistrates Court this week heard the woman, 21, posted a picture of her former stepfather and captioned it "This man is a pedophile, so keep your children away from him".

A relative of the man, whom the court heard served time for abusing the girl, alerted him about the post, which accumulated eight "likes" and 30 comments.

Police prosecutor Steve de Lissa said the incident was soon reported to police, with the man telling officers he was "upset" and thought he would have to leave town because of it. When contacted by police, the woman admitted to making the post.

She told police she did it because she was angry her mother had rekindled a relationship with the man after his release from jail.

Magistrate Graham Lee acknowledged that what the woman wrote on Facebook was the truth but warned her that harassment via social media was "very serious".

The woman pleaded guilty to using a carriage service to menace, harass or cause offence and was placed on a $600 good behaviour bond for 12 months.