Rio Tinto chief executive Sam Walsh says Australia should look to Asia when trying to determine what its corporate tax rate should be in the future. 
Speaking in Melbourne on Wednesday, Mr Walsh joined the chorus of business leaders calling for Australia's corporate tax rate to be lowered.
Mr Walsh pointed to the fact New Zealand, Canada, Britain and South Africa had cut corporate tax rates in recent years.
He said Australia was falling behind the trend.
"Australia's tax system has fallen out of step with the rest of the world, given that in the past decade a host of countries have cut their corporate tax rates," he said.
"The public debate on reforms to the Australian economy and the tax system is therefore timely."
Australia's corporate tax rate is 30 per cent for large companies like Rio.
Mr Walsh said corporate tax rates were closer to 21 per cent in Asia.
He said Australia should look directly north for its guidance on corporate tax changes.
"As a suggestion, look closer to home, to Asia, than to a theoretical OECD or European average," he told alumni at the Melbourne Business School.
"The average corporate tax rate in Asia is closer to 21 per cent. A worthy goal to consider and continue Australia's pivot towards, and engagement with, Asia."
Mr Walsh is expected to visit his former school, Brighton Grammar, while in Melbourne.
Rio shares closed 37&cent; lower at $46.55.