Australia's federal politicians have been outed as the country's most eager property investors, casting doubt on their willingness to rein in negative gearing.

The controversial practice allows taxpayers to use tax losses from rental properties to cut their taxable income. Critics argue it contributes to Australia's house affordability crisis.

Around one in seven Australian taxpayers own rental properties, but among federal politicians it is at least one in three.

Figures compiled by property authors Lindsay David, Paul Egan and Philip Soos show federal politicians own an average 2.4 properties each, including their family homes.