The Queen has made a personal donation to a relief fund set up by the Queensland state government.
Buckingham Palace says the funds will go directly to the Premier of Queensland's flood relief appeal.
But the Palace would not say how much money the Queen had donated.
Last week, the Indonesian government donated $1 million to State Premier Anna Bligh's disaster relief appeal.
Foreign Minister Marty Natalegawa said the government was impressed by the resilience of the people of Queensland and hoped the "modest sum" would help residents recover.