Sales were down more than six per cent in May as the sector continued to grapple with the effects of the COVID-19 pandemic and a shortage of microprocessors which has impacted the availability of new vehicles across the globe.
The Federal Chamber of Automotive Industries said 94,383 vehicles were sold across Australia last month, down 6.4 per cent on the same month last year.
"The global automotive industry continues to be plagued by a shortage of microprocessor units and shipping delays," FCAI Chief Executive Tony Weber said.
"This issue is not unique to Australia. Car makers continue to report high demand across dealer showrooms and online marketplaces.
"Pandemic interruptions continue to impact manufacturing and conflict in Ukraine has disrupted vehicle component supply.
"Monthly sales figures are also dependent on shipping arrivals which continue to be uncertain.
"We do not expect supply chains to stabilise until these issues are resolved."
The fall in sales in May left the market for the first five months of 2022 down 4.1 per cent at 437,884.
Toyota was the top-selling company last month with 22,813 ahead of Kia on 7307, Hyundai on 7063, and Mazda on 6474.
The Toyota Hi-Lux was the best-selling vehicle with 5178 retailed ahead of the company's RAV4 on 3925 and the Ford Ranger on 3751.
Demand for electric cars continued to be strong with 925 sold for the month, taking sales to the end of May to 8543, more than four times the level at the same time in 2021.
However sales of Tesla's Model 3 were down sharply from 52 in April to 12 last month.