At 1116 GMT the rand traded at 17.2750 against the dollar, 1.92% stronger than its previous close.
Ramaphosa beat former health minister Zweli Mkhize to secure a second five-year term as ANC leader, paving the way for him to contest the presidency again at 2024 elections.
His re-election campaign was dogged by the "Farmgate" scandal that broke in June involving large sums of foreign currency found hidden at his private game farm.
Ramaphosa has denied wrongdoing and has not been charged with any crimes, but it raised questions, making him more vulnerable within the party.
However, he shrugged it off on Monday by cementing his position as the country's most popular politician.
Analysts have said the ANC's reformist agenda and its ability to introduce some necessary changes were at stake, with markets widely pinning hopes on a Ramaphosa victory.
"The good thing about (the election outcome) is that it suggests continuity in economic policy," finance minister Enoch Godongwana told reporters.
The government's benchmark 2030 bond was stronger, with the yield down 7.5 basis points at 10.140%.
(Reporting by Anait Miridzhanian and Bhargav AcharyaEditing by David Goodman and James Macharia Chege)
