The African National Congress (ANC), which has a large majority in parliament, nominated Mr Ramaphosa, a wealthy former businessman, “to be elected as the new President of the Republic of South Africa”.
After being voted in, Mr Ramaphosa will address lawmakers gathered in the parliament in Cape Town, the party said in a statement.
Jacob Zuma resigned on Wednesday as the ANC finally turned against him after a nine-year reign dominated by corruption scandals, economic slowdown and plummeting electoral popularity.
Mr Zuma railed against the ANC for “recalling” him from office and – when he at first refused to resign – then threatening to oust him via a parliament no-confidence vote.
In an earlier TV interview on Wednesday, said he had received “very unfair” treatment from the party that he joined in 1959 and in which he had fought for decades against apartheid white-minority rule.
Mr Zuma had been in a power struggle with Mr Ramaphosa, his deputy president since in 2014.
Mr Zuma’s hold over the ANC was broken in December when his chosen successor – his former wife Nkosazana Dlamini-Zuma – narrowly lost to Mr Ramaphosa in a vote for the new party leader.