New Zealand took full advantage of winning the toss and sending South Africa in to bat on an overcast day in conditions which helped their seam bowlers.
South Africa made a bad start, losing their first two wickets for three runs, and never recovered despite a restrained innings of 60 by Herschelle Gibbs, who shared stands of 49 with Jacques Kallis (22) and 76 with Ashwell Prince (37).
The tone was set by New Zealand opening bowlers James Franklin and Shane Bond, who both took an early wicket and were mainly responsible for South Africa scoring only 13 runs in the first 12 overs.
Bond finished with two for 26 in ten overs, while left-armer Franklin took one for 16 in seven.
Medium-pacer Craig McMillan was the most successful bowler, however, taking three for 23.
McMillan took the key wicket of Gibbs, who was bowled by a ball which deflected off an inside edge and his right thigh and followed up by dismissing Prince and Mark Boucher, both caught in the deep as they tried to lift the scoring rate.
New Zealand lost by six wickets in a one-sided contest against Sri Lanka when they were in early trouble after deciding to bat first.
For South Africa, the innings was a contrast to their free-scoring display when they hammered 356 for four against the West Indies at the same ground Tuesday.
After pounding 14 sixes and 24 fours against the West Indies, South Africa were restricted to 11 boundary hits Saturday - three sixes and eight fours - as they struggled to make clean contact against disciplined bowling on a slow pitch.