The march to Union Buildings, the official seat of government, was organised by a coalition of opposition parties following nationwide rallies against Zuma last week. At 74, Zuma's nearly seven years in office as South Africa's President has been littered with accusations of cronyism and cultivating inappropriate relations with wealthy business tycoons.
The rand has tumbled more than 11 percent since March 27, when Zuma ordered Gordhan to return home from overseas talks with investors, days before firing him.
Zuma's office said the president would take part in his 75th birthday celebrations on Wednesday at a public venue in the township of Soweto, near the commercial hub of Johannesburg.
Although SACP leaders shared the same stage with Zuma in memory of Hani, the SACP said it has not changed its plea for Zuma to resign.
The protest united groups with sharply different ideologies.
The latest jolt came when Zuma on March 30 dismissed Finance Minister Pravin Gordhan, who was seen as a prudent steward of fiscal affairs.
'Only time will tell' on improving US-China trade
China and the U.S. agreed that Pyongyang's programmes are a serious problem, but have not seen eye-to-eye on how to respond. White House Press Secretary Sean Spicer mentioned that the two leaders had also discussed human rights issues.
Opposition parties have vowed to keep the pressure on.
Tens of thousands, many of them supporters of the main opposition Democratic Alliance (DA) attended protests on Friday in major cities in the biggest show of discontent with Mr Zuma. The parties said the march was open to anyone to join.
Some top ruling party leaders openly criticized the decision.
Holomisa added that the recent two credit downgrades to junk status make South Africa an unsafe investment destination and the effects will be felt by all.
For now, however, it looks as if Zuma may succeed in entrenching his sleaze-tinged power structure in what was once the party of Nelson Mandela. He paid back some money after the Constitutional Court ruled against him previous year. Opponents described the remark was an affront to legitimate protest. Again, this time around, he has not only waved away calls by veterans of the liberation struggle, the Congress of South African Trade Unions (COSATU) unions and South Africa's Communist party (a historical ally of the ANC) for him to demit office, but seemed likely to survive a confidence vote in parliament later this month. The ANC has said it wouldn't allow its members to vote in favor of the motion. The legal challenge has raised the possibility of a delay in the vote, according to South African media.