"Now it's time to bring bread on the table," the 31-year-old told a crowd of 30,000 supporters, reprising his demands for the seizure of farms from white owners and the nationalisation of mines.
The leader of the Economic Freedom Front (EFF) is infamous for his controversial statements, and has used a spate of miners' strikes to attack the ruling African National Congress, which booted him from its ranks two years ago.
Malema's inflammatory statements have gained currency in a country with seven million unemployed. Twenty years on from the end of apartheid, South Africa's "black people are still not free," he said.
"We have the responsibility to end the pain of our people, we are saying enough is enough, now it's time for economic freedom... Time to rescue South Africa from deep levels of inequality."
More From This Section
"You must no longer be ashamed," he told the crowd.
He also reiterated his support for gold miners, who have been on strike over wages for the past month, and whom Malema visited on a recent tour to drum up opposition to the government.
The EFF was created in 2012 after Malema and his allies were kicked out of the ANC for criticising the party leadership.
The ANC, in power since the end of white-minority rule in 1994, is almost certain to win elections on May 7, giving President Jacob Zuma a new five-year term. But it faces growing frustration from voters and increased competition from opposition parties.