Australia is the third most popular destination for ultra-rich Chinese to invest wealth offshore and it's closing the gap on other countries, a new report shows.

As interest in the top two investment destinations, Hong Kong and the United States falls by 18 per cent and 3 per cent respectively, there has been a 7 per cent jump in Chinese private wealth flowing to Australia.

At the same time China's pool of private wealth swelled to 165 trillion Chinese yuan (about $31 trillion) in 2017 – six times what it was a decade ago, and twice the size of China's GDP, according to the Bain and Company and China Merchants Bank's China Private Wealth Report.

There are 1.6 million high net worth Chinese, with at least 10 million Chinese yuan to invest, the report found. This represented a leap from 180,000 in 2006.