West Indies, who finished fifth at the World Cup, thus have won the One-day series 2-1 which was hurriedly-arranged after both teams made early exits from the World Cup.
Inserted into bat by South African captain Alison Hodgkinson, the West Indies batswomen found the going tough against some disciplined bowling from South Africa and were shot out for a paltry 90 in just 34.4 overs.
Alicia Smith, Lonelle de Beer and Charlize Van Der Westhuizen did the maximium damage sharing eight wickets between them. Nadine George was West Indies' standard-bearer with 22.
Needing 91 for victory, opener Cri-Zelda Brits led the way with an unbeaten 62 not out from 71 balls as the Proteas knocked off the runs in 24.4 overs.
Brits' fellow opening partner Daleen Terblanche retired hurt on 10 before talented Johmari Logtenberg added 15 to hand an impressive victory for South Africa which was only their second win in ten completed ODIs over the past month.
Brief scores: West Indies 90 all out (34.4 overs). South Africa 91/0 (24.4 overs).