A woman who was sexually assaulted as a child says she is angry the trial of her alleged attacker has been aborted.

Debra Wooby says she was abused as a 13-year-old in 1975 while living at the former St Cuthbert's Children's home at Colac, south-western Victoria.

The alleged offender, a Queensland man, was committed to stand trial on charges of carnal knowledge and indecent assault.

But the Office of Public Prosecutions (OPP) has now told Ms Wooby the case has been dropped because of the statute of limitations.

She believes her case has been mishandled and that it might discourage victims of sexual abuse from approaching the Royal Commission into child sexual abuse.

Ms Wooby says she is devastated.

"Obviously I think they stuffed up," she said.

"How can I have gone through a committal and committed to trial to end up with 'No, you can't do anything now'.

"I thought once it was committed for trial, all that must have been okay."

Ms Wooby is calling on the Prime Minister to intervene

"She needs to get all the attorneys-general together. They all need to come together and they need to work something out. Because she's said we're having a royal commission but, after that, sorry you aren't going to get anywhere," she said.

"Where's the justice?"