"I think I'm half-man, half-croc," he told The Star of his leap on Monday at Crocodile Creek, which is home to more than 5000 Nile crocodiles.
Mokoena, whose Sesotho surname translates as "he who swears by a crocodile", told the newspaper it was something he had wanted to do for a long time.
"It was about testing myself, my mental strength and overcoming the fear. As an athlete, I'm constantly pushing myself, embracing that animal instinct to go as far as I can," he said.
Mokoena has many tattoos of crocodiles on his body, and the words "Crocodile Bites".
"Crocs are most dangerous when in the water as they can propel themselves upwards to four metres with force," Peter Watson, an expert on crocodiles, and the owner of the creek told The Star.
"It was important that Mokoena understood that the animals could be unpredictable and that it was in his best interests to jump as far and high as he could," he said.
Mokoena is reportedly in training for the Diamond League, with his first appearance scheduled on May 18 in Shanghai.