The fallout from the US numbers also weighed on the rand, which fell as much as 1.5% to a 10-day low against the greenback.
The Top 40 index of blue chips dropped 2.35% to 23605, its lowest close since May 26. The broader All Share index fell 2.13% to 26558.
Financial companies and miners were hit particularly hard.
"The (US jobs) numbers came out worse than expected and that sparked a sell-off," Henre Herselman of BoE Private Clients said.
"It has weighed on commodity prices, and the rand weakened a bit on the back of that."
US non-farm payrolls data showed that 431000 workers were hired in May, well below the 513000 forecast by a Reuters poll. Investment bank Investec fell 2.5% to R56.81 while African Bank Investments, the mass-market lender, dropped 3.5% to R20.83.
Impala Platinum, the world's second-largest producer of the precious metal, tumbled 4.8% to R182.50.
Underscoring the shaky outlook for the equity market, private hospital group Life Healthcare priced its initial public offering at the bottom of its lowered range.
The rand tracked the weak tone across financial markets, touching a session low of R7.79 against the dollar, its weakest level since May 26 according to Reuters data.
By 7pm, the rand traded at R7.77/$, 1.28% weaker than its previous close in New York of R7.68/$.
Government bonds also headed lower, with the yield on the 2015 bond (R157) subsequently climbing 11 basis points to 8.1% while that on the 2036 note (R209) rose seven basis points to 8.950%.
Global markets remain uncertain about a general recovery from last year's recession, and analysts expect volatility to persist for some time.
On Friday, the pan-European FTSEurofirst 300 index shares closed down 1.9%. US stocks dropped more than 2%, with the Dow industrials falling briefly below the 10000 level. - Reuters