The head of the Australian Defence Force's Catholic diocese has been found not guilty of sexually abusing five students more than 40 years ago.

Catholic bishop Max Davis, 70, was on trial in the Perth District Court accused of six counts of indecent dealings with male children between 1969 and 1972, when he was dormitory master at St Benedict's College in New Norcia, north east of Perth.

He stood aside from his duties as Catholic Bishop of the Australian Defence Force (ADF) when he was charged two years ago.

The prosecution alleged Bishop Davis performed indecent acts on five students aged between 13 and 15 years old.

One former student testified he was sexually abused while he was being examined in the first-aid room because he had injured his groin playing football.

He said the abuse was by "Brother Max", who was a dormitory master at the college.

Another man testified he was abused when he "took a sickie" and stayed in his bed in the dormitory, and thought it was part of a medical examination.

However the defence told the court while there was "no dispute" the complainants had been sexually abused at the college, Bishop Davis was not responsible.

A jury on Monday deliberated for about four hours before finding Bishop Davis not guilty of all six charges.

Bishop Davis took the stand on Thursday and denied, under oath, that he sexually abused any of the teenage boys at New Norcia.

In his evidence he said he had no "independent recollection" of any of the complainants.

He also testified he had no sexual interest in children, and was appalled when, in 1971, he was told by a group of students that another clergy member was behaving inappropriately towards boys.

Bishop Davis said he immediately reported the concerns to the Abbot, who was in charge, and the priest was removed from the school that day.

He also told the court he was never referred to as "Brother" because he was not a member of any order.

Bishop Davis was a teacher as well as dormitory master at the school and in 1971 was ordained a priest.

Bishop Davis made no comment as he left court after the verdict.