An organisation which hunts Nazi war criminals has slammed the Australian High Court for refusing to extradite Charles Zentai to Hungary.

The Jerusalem-based Simon Wiesenthal Centre says it is a sad day for Australia.

"Today is a sad day for Australia and for justice, but most of all for the Nazis' victims, their families and those who empathise with their suffering," the centre's Israel director, Efraim Zuroff, said in a statement.

Mr Zentai, a 90-year-old Perth man, is wanted for questioning in relation to the torturing and killing of a Jewish teenager while he was serving in the Hungarian army in 1944.

He has always maintained his innocence.

The court ruled he could not be extradited because the offence of committing a war crime did not exist at the time of the alleged incident.

The Wiesenthal Centre says the court's decision appears to ignore numerous legal precedents.

"It signals a dismal conclusion to Australia's totally unsuccessful efforts to bring to justice any of the numerous Nazi war criminals who found refuge in the country," Mr Zuroff said.

abc.net.au