G20 protests kicked off Friday with Tibetan freedom campaigners unveiling huge black balloons and Oxfam members dressing up as "world leaders" for a beach party.
A small group from the Australian Tibet Council and Students for a Free Tibet released two huge balloons in New Farm, along with a large banner saying "China Fails Human Rights.
G20 Unite For Tibet", The Brisbane Times reported.
Protest organiser Kyinzom Dhonghue said China remained "an authoritarian state that continues to oppress the Tibetans".
Meanwhile, at the Wheel of Brisbane, people wearing comically large heads bearing the likeness of Indian Prime Minister Narendra Modi, US President Barack Obama, Australian Prime Minister Tony Abbott, British Prime Minister David Cameron, German Chancellor Angela Merkel, Chinese President Xi Jinping and South African President Jacob Zuma were in lifeguard costumes designed by Oxfam.
The charity is urging the leaders to use their power at the G20 Summit to address inequality.
"The tide of inequality is a critical issue not only affecting the world's poorest nations, but almost all of the G20 countries as well," Oxfam chief executive, Helen Szoke, said.
"Getting people to South Bank dressed up as our world leaders in lifeguard costumes is a light-hearted way of making a very serious point."
Both groups are also expected to hold protests Saturday.