In his opening address to a conference to choose the party's leadership for the next five years, Mr Zuma said two downgrades by international ratings agencies this year did not mean South Africa was in trouble.
"We want to dismiss the perceptions that our country is falling apart because of the downgrades," he said. "We continue to do our development work, we continue to plan for a recovery."
At the conference this week held in Bloemfontein, Mr Zuma, 70, is expected to garner enough support to head off a challenge to his party leadership from Deputy President Kgalema Motlanthe. Retaining the leadership of the African National Congress (ANC) puts Mr Zuma in pole position to secure a second five-year term as South Africa's president in elections in 2014.
Spicing up the contest for top jobs, former mineworkers' leader and anti-apartheid hero Cyril Ramaphosa, now one of South Africa's richest men, is to stand for the post of ANC deputy president, currently held by Mr Motlanthe.
In his speech, Mr Zuma said the government was relying on its long-term National Development Plan to undo the "glaring and deep" inequalities left by decades of apartheid rule.
South Africa's economy is forecast to grow 2.5% this year, well short of the 7% the government says it needs to make a serious dent in 25% unemployment.
Mr Zuma also called for an end to internal faction-fighting and corruption in Nelson Mandela's 100-year-old liberation movement.