Overnight co-leader Strydom managed to hold on to a share of the lead at the turn on Sunday despite a roller-coaster front nine, which began with five successive pars before his first birdie at the sixth was followed by a bogey on the par-three seventh, a birdie at the eighth and a double bogey on the ninth.
Strydom then found the form and consistency he had lacked on the front nine, picking up shots at the 10th, 11th, 13th and 14th to open up a three-shot lead.
The home favourite produced some vital par saves on the way home to sign for a 69 and finish the tournament on 18 under par.
Spain's Adrian Otaegui finished alone in second on 16 under after carding four birdies and no bogeys in his final-round 68.
Englishman Laurie Canter was another shot further back in third following his 64 - which contained an eagle, seven birdies and one bogey - one stroke ahead of Aaron Cockerill, Oliver Bekker and Branden Grace.
Strydom is looking forward to playing on the DP World Tour more regularly following his victory at Leopard Creek.
"It's nice... I think my plans just changed a little bit," said the 37-year-old.
"I was playing on the Sunshine Tour next year but all of a sudden it's the DP World Tour now. Probably got to get my flights and everything ready for Abu Dhabi then!"