South Africa chased down the Windies' score of 173-7, securing a comfortable victory with 13 balls to spare as both sides prepare for next month’s T20 World Cup.
Markram’s runs came off 47 balls and he was ably supported by Ryan Rickelton, who made 40 for an unbeaten second-wicket partnership of 93.
Shimron Hetmyer was the top scorer for the Windies, coming in at number six to hit a brisk 48 off 32 balls and feature in a 74-run stand with Rovman Powell that saw the tourists post a decent target.
The second of the three-match series is in Pretoria on Thursday, followed by a last clash on Saturday at the Wanderers in Johannesburg.
Both countries then head to the World Cup where the West Indies start against Scotland at Eden Gardens in Kolkata on February 7 while South Africa’s first match is against Canada in Ahmedabad on February 9.
