Hundreds of people joined in the Sydney electorate of the prime minister, calling on the federal government to intensify and act on climate change.
The signals asking Prime Minister Scott Morrison to end coal mining and move to renewable energy were some of the messages that more than 500 protesters had for his government in Cronulla Park on Saturday.
Local resident Aref Taleb said it was time for Australia to change its ways and the protest was part of the nation's youth who refused to "sit and wait for our leaders" to act.
The executive director of the NSW Nature Conservancy, Kate Smolski, said the state was struggling with the seasons of fire and drought and pointed to the country's "addiction" to fossil fuels.
"It's time to get coal out of politics forever and feed Australia back with clean energy," Ms. Smolski said in a statement on Saturday.
The Australian left lobby group GetUp! He warned that Mr. Morrison could lose the best position if he does not put the climate at the top of his agenda in the next election.
The demonstration comes before Mr. Morrison's plan to get rid of the National Energy Guarantee at a meeting of the party hall when parliament resumes next week.
It will also rule out the legal consecration of the commitments of the Paris Agreement.
Those goals would see Australia reduce its carbon emissions to 26-28 percent from the 2005 levels by 2030.
But a spokesman for the prime minister says the government remains committed to meeting its goals in Paris.
The protest was one of several across Australia organized on Saturday by an alliance of environmental groups and activists, including Greenpeace, NSW Nature Conservation Council, 350.org and GetUp!