After losing the toss, the visitors posted 287-9 in their 50 overs thanks to half-centuries from Tony de Zorzi (78 from 92 balls) and Khaya Zondo (60 from 69).
De Zorzi shared an opening stand of 98 with Ryan Rickelton (47 off 52).
Andile Phehlukwayo made 29 from 25 balls, while skipper Heinrich Klaasen chipped in with 17 off 15.
Wellington Masakadza (4-44) and Tanaka Chivanga (3-43) were the pick of the Zimbabwe bowlers.
In reply, the hosts were bowled out for 251 in 47.2 overs.
Kevin Kasuza top-scored with 66, while Phehlukwayo starred with the ball for SA A, taking 4-32.
#3rdOneDay | WICKET! Donald Tiripano (48) b Phehlukwayo
After 43.5 overs, 🇿🇼 XI are 236-8, need 52 runs in 37 balls
Live streaming 👉 https://t.co/JsXicdOZn1#ZIMXIvSAA | #VisitZimbabwe pic.twitter.com/yZIRX1Sg9i
— Zimbabwe Cricket (@ZimCricketv) April 29, 2022
The T20 series between the teams begins on Monday at the same venue.
