One in five Chinese Australians say they have been physically threatened or attacked in the past year because of the COVID-19 pandemic and tensions in Australia's relationship with China, a survey by the Lowy Institute think tank reported.

The findings prompted a call from the Chinese Australian Forum, a community group, for national leadership to tackle racism as Australia deals with a more assertive China, and also recognition that the Chinese community in Australia is diverse in its political views and origins.

Around 5% of Australia's population of 25 million claim Chinese ancestry, the national census shows. Half of the Lowy survey respondents were born outside mainland China, in places including Hong Kong, Malaysia and Taiwan.