"Once again we will return to the United Kingdom with fond memories of our time here and the warm Australian welcome we have received on our 16th visit to this beautiful country," the queen said as she and the Duke of Edinburgh attended a riverbank party expected to draw around 200,000 guests.
The royal couple spent 11 days in Australia, and Buckingham Palace denied the idea it was their final visit. The queen is 85 and her husband is 90.
Britain's The Daily Telegraph said the duke good-naturedly grabbed a spatula and took a turn flipping steaks and shrimps on the barbie, although he declined to sample the seafood.
The royal party was due back in London Sunday, the newspaper said.