The assembly plant will initially be building medium-sized commercial trucks, a company spokesman said on Tuesday.
The Benoni plant, situated in South Africa's economic hub Gauteng, has been assembling trucks since July, ahead of a formal launch in September, Deon Sonnekus said.
"This is the first time that Hyundai has set up an assembly plant in South Africa," Sonnekus said, adding that the company expects to also assemble pick-up trucks from next year.
South Africa is the continent's leading automotive manufacturer and aims to build 1.2 million vehicles by 2020.
However, labour strikes and slowing economic growth in recent months have curbed output at the local plants of some of the world's main carmakers, including Ford, Toyota and BMW.