The 59-year-old man was killed on Saturday at Malelane Gate, one of the most trafficked entrances to the national park, according to the police.
Two of the man's grandchildren, five and eleven years old, were attacked by the elephant when they took pictures and filmed the animal, which was inside the park. When the children ran away from the elephant, they fell, and the elephant attacked the eleven-year-old boy with its trunk.
When the man tried to protect his grandchildren, he was trampled by the elephant before it left them and returned to the national park.
"The police and rescue personnel were called to the scene, but unfortunately, the man had already died from his injuries. The boy was lightly injured in the leg," says the police in a statement.
According to the national park organization San Parks, the deceased man is South African.
With its 20,000 square kilometers of savannah, Kruger is the largest national park in South Africa. With the exception of fenced camps and a few picnic areas, it is prohibited for visitors to leave their vehicles.