At 1512 GMT, the rand traded at 18.9550 against the dollar, nearly 0.5% weaker than its previous close.
The dollar last traded around 0.22% stronger against a basket of global currencies.
"With no high impact South African specific data scheduled throughout the week, U.S. and Chinese influences will play a major role," said DailyFX analyst Warren Venketas in a research note.
The rand had jumped over 1% on Monday following encouraging economic data out of China, its biggest trading partner.
Like other emerging market currencies, the risk-sensitive rand often takes cues from global economic factors such as U.S. monetary policy in the absence of major local drivers.
Shares on the Johannesburg Stock Exchange were little changed, with the broader all-share index and blue-chip Top-40 index ending near their previous close.
South Africa's benchmark 2030 government bond was marginally weaker, with the yield up 1 basis point at 10.400%.
(Reporting by Tannur Anders and Bhargav Acharya; editing by Christina Fincher and Ken Ferris)
