Cape Town - The Blitzboks made it two from two at the London Sevens after beating Canada in their second pool fixture on Saturday.
South Africa opened the scoring thanks to a try from Werner Kok in the opening minute. Branco du Preez added the conversion for an early 7-0 lead.
Canada hit back soon after with Matt Mullins crossing for a converted try but Blitzbok captain, Siviwe Soyizwapi, soon has his side back in control with a converted score and a 14-7 lead.
Canada drew level on the stroke of half-time with Luke McCloskey the scorer and Nathan Hirayama adding the conversion to see the teams into half-time at 14-all.
The Blitzboks showed their class in the second half however with Kok getting his second and Kurt-Lee Arendse, JC Pretorius, Impi Visser and Selvyn Davids crossing the whitewash.
Davids added three conversions as South Africa ran out 45-14 winners.
Earlier, the Blitzboks won their opening match at the tournament by easily defeating Japan 49-0.