Magistrate Tebogo Thupaatlase says the state failed to prove its case.
"The accused is found not guilty," he said.
"None of the evidence presented established that there was anything that a reasonable man in the position of the accused, on that night would have foreseen."
In 2014, the businessman was involved in a crash with a taxi, in which passenger Phumzile Dube died.
Initially, the National Prosecuting Authority declined to press charges but that decision was reviewed last year after AfriForum announced its intention to institute a private prosecution.
Zuma had testified that his car had spun out of control after hitting a pool of water.
Former president Zuma was at the court to support his son.
"The court assessed the situation well and the court's decision has made me happy," Jacob Zuma told reporters after the ruling.
- Additional reporting AFP
Judgment will be delivered on Friday in Duduzane Zuma's culpable homicide and negligent driving case.