The funding will go to organisations able to deliver desperately needed food, medical supplies and other lifesaving support, the federal government said in a statement on Sunday.
The new package of support includes $6 million for the United Nations World Food Program for the provision and distribution of food supplies and $5 million for UNICEF for nutritional support for children at risk of starvation.
The International Committee of the Red Cross will also receive $5 million to help those in Gaza meet essential needs, including access to health care.
An additional $2 million for relief support with the UK will be donated through an existing partnership arrangement, while $2 million will go to the Jordan Hashemite Charity Organisation to provide medical supplies to support the operation of field hospitals in Gaza.
Australia has so far committed $130 million in humanitarian assistance to help civilians in Gaza and Lebanon since October 7, 2023.
But the federal government has been criticised for not doing enough in addressing what the UN has described as worsening famine conditions in Gaza.
About 90,000 people turned the Sydney Harbour Bridge into a sea of Palestinian flags on Sunday while tens of thousands more held similar protest in Melbourne and Adelaide ins support of Gaza.
Foreign Minister Penny Wong said Australia has "consistently been part of the international call on Israel to allow a full and immediate resumption of aid to Gaza".
"The suffering and starvation of civilians in Gaza must end," she said.
"Australia will continue to work with the international community to call for an immediate and permanent ceasefire, the release of hostages and a two-state solution - the only path to enduring peace and security for the Israeli and Palestinian peoples."
Prime Minister Anthony Albanese is eying global moves to recognise a Palestinian state after British Prime Minister Keir Starmer said the UK would do so unless Israel secured a ceasefire and increased humanitarian aid into Gaza.
The UK's stance comes after France became the first G7 country to say it would recognise Palestine ahead of a UN general assembly meeting in September. It was followed by Canada.
Mr Albanese has said that while the world was horrified at Hamas' October 7, 2023, attack on Israel, which resulted in thousands of deaths and some 200 people being taken hostage, the subsequent war had cost too many innocent lives.
He's also said it was a matter of "when, not it" Australia would recognise a Palestinian state, under Labor's policy to back a two-state solution in the Middle East, with the condition that Hamas - which Australia considers a terrorist organisation - steps back from any governing role in the Strip.
Gaza's health ministry says 60,000 people have been killed during Israel's counteroffensive.
Israel has restricted food and medical supplies from entering Gaza, where it controls all entry points, to put pressure on Hamas.
International pressure is mounting on the nation state to let in more humanitarian aid, as deaths attributed to malnutrition rise.
Israel denies there is starvation in the besieged strip despite international human rights groups branding Israel's offensive in Gaza a genocide and attributing deaths to starvation.
