A lecturer at the Australian National University was stood down after an internal investigation revealed he maintained a sexual relationship with a student.

The revelations sparked a review of practices within the esteemed Crawford School of Public Policy with the university accepting his serious misconduct was unacceptable.

According to a confidential report seen by Fairfax Media, the man failed to disclose his intimate relationship with the student and continued to see her while supervising her study.

The report, prepared by the university's human resource division, revealed the teacher was immediately suspended with pay in August 2015 while allegations were investigated. He no longer works at the university.

The misconduct, detailed in stream of text messages and email correspondence, was only brought to the university's attention when the student complained about the emotional trauma it caused her.