Liebenberg, 33, who was making her first appearance in the competition, claimed the triumph in the Under 1.63m Division.
The bikini beach models were judged on two rounds where items such as overall physique appearance, femininity, symmetry and personality were used as part of the judging criteria.
“I was completely shocked,” she said of her victory.
“It was never about winning; it was all about getting there (the competition). I was very humbled by the whole experience.
“You have no idea what it takes to get there until you go through the journey yourself.
“The best feeling in the world (that I will never forget) was when I saw my husband jump up and cheer when I won. It made me want to cry with pride and happiness as we had worked so hard and sacrificed so much to get there.
“The saying of blood, sweat and tears could never have been truer,” she said.