The benchmark JSE Top40 index was up 0.88 percent at 46149.85 points, while the broader all share index gained 0.63 percent to 52990.08 points.
Resource stocks got a lift from a rise in metals prices with diversified miner BHP Billiton the biggest gainer among the blue chips, rising 5.23 percent to close at R221.41.
Copper prices rose more than 2 percent, on upbeat jobs data from the US.
Local resource firms were buoyed even further, as they earn their revenue in dollars and pay their costs in rand.
“Resource stocks are going to enjoy that... the weaker rand,” said Northshore Capital fund manager, Mark Loubser.
Steinhoff International, a furniture and general retailer with units in Europe, Britain and the US, added 4.88 percent to R67.75.
Banks were among the losers as the credit downgrade and lingering political tensions weigh on their business prospects. The banking index fell 2.38 percent to 6944.50 points.
Meanwhile, US stocks rose in early trading yesterday, with the Nasdaq hitting a fresh all-time high on strong US private sector jobs data.
The Dow Jones industrial average was on track for its best day since March 1 in a broad rally.