Judge Michael Shanahan remarked Duy Hung Tran's gender disorder could explain what he was doing in the women's toilets but it did not explain Tran's voyeurism.

He noted that at the time Tran was on a probation order for a similar offence.

In the District Court in Brisbane, Tran, 35, pleaded guilty to making an observation in breach of privacy, on November 5, 2008.

Prosecutor Dennis Kinsella told the court at the time Tran and his wife ran a waxing and fingernail treatment salon at Burpengary, north of Brisbane.

He said Tran had access to the staff toilets and a woman, 18, noticed Tran follow her into them.

The woman then saw Tran looking at her over the top of the cubicle.

Mr Kinsella said the matter was reported to security staff but at the time police were not notified.

The matter came to light when police interviewed Tran about another public nuisance accusation when he was found in a women's toilet.

Mr Kinsella said Tran was placed on a probation order earlier in 2008 for another similar offence.

Barrister Scott Lynch, for Tran, said his client had gender and as well as sexual dysfunction problems which were now being treated by a psychologist.

He said Tran had left the business and moved to a country town.

Mr Lynch said Tran had previously completed probation and would benefit from more.

Judge Shanahan said the disorders could explain why Tran was in female toilets but did not explain his voyeurism.

He placed Tran on two years' probation with special conditions he get treatment for his disorders and did not record a conviction.