Extinction Rebellion (XR) picketed outside the building of the Department of Mineral Resources in Pretoria on Friday.
The 80 or so protesters called on the government to make switching to renewable energy an emergency.
They also called on government to be truthful about the state of human-caused climate change in the country and to reduce net carbon dioxide emissions to zero by the year 2025.
The protest was supported by several organisations, including Right2Know and Mining Affected Communities United in Action.
Extinction Rebellion launched in the United Kingdom in 2018 and has since become a worldwide movement dedicated to fighting human-caused global warming. The movement has been inspired by Swedish teenage environmental activist Greta Thunberg.
A protest leader read a letter addressed to the Minister of Mineral Resources Gwede Mantashe.
The letter stated: "This business-as-usual scenario has put the planet on to a trajectory that places us in a perilous situation. We need our government to tell the truth and declare an emergency. Today we are calling on our government to reverse its inconsistent policies around fossil fuels and make the bold steps that are required to a just transition to renewable energy."
Mitchell Black, an XR member, said: "South Africa has some of the lowest climate change literacy in the world, where only 14% of our population even knows that climate change exists ... The government is prioritising businesses and business developments instead of trying to build resilient food and water systems for its people."
Deputy Director General of the Department of Mineral Resources Ntokozo Ngcwabe addressed the protesters: "I am here to receive this letter on behalf of the minister. We are going to submit this letter to him. He is the responsible minister and will be responding to you."
XR has given Mantashe until January to respond.