An Australian man has been sentenced to 500 lashes and a year in prison in Saudi Arabia for breaking the country's strict blasphemy laws during a Haj pilgrimage last month.

Australia's Department of Foreign Affairs said it was very concerned about the well-being of the man, named in media reports as Mansor Almaribe, a 45-year-old father of five.

"The Australian Government has a universal policy of condemning the use of corporal punishment amounting to torture, or cruel, inhuman or degrading treatment or punishment," a spokeswoman for Foreign Minister Kevin Rudd said in a statement.

Australia's ambassador had contacted the Saudi government, seeking leniency, she added.

"Five hundred slashes on his back and he has back problems. I wouldn't think he'd survive 50," one of the man's sons, Mohammed Almaribe, told the Australia Broadcasting Corporation.

A spokesman from the Saudi justice ministry did not respond to calls and messages for comment. The Australian Associated Press said the man had been accused of insulting the companions of the Prophet Mohammad.

The sentence comes a day after a Chinese court sentenced an Australian businessman to 13 years in prison for fraud in a case that raised fresh foreign concerns about China's murky legal system.