A Queensland priest once accused of child sexual assault has attempted to gain access to the recorded police interview with the alleged victim so he could sue her for defamation.

The man, who was never charged after an investigation 15 years ago, used freedom-of-information laws to apply for access to two cassette tape recordings and a 99-page police report, Fairfax News reports.

His request was denied late last year on the grounds that disclosure was against the public interest.

Last month the Office of the Information Commissioner upheld his appeal against that decision.

The former priest told the OIC he was pursuing defamation action against the complainant as well as appealing a decision made by the Catholic Church to remove him from active ministry and placed in early retirement.

The former priest says his reputation is unjustly damaged and his mental and physical wellbeing has suffered.

He told the OIC he expects documents from the police investigation would "contradict" the complaint and "demonstrate it was false".

But the OIC denied his appeal on the grounds that it could potentially dissuade people from coming forward with complaints in the future.