Jan-Friederick Bredenhand, 30, was pulled into the lions' pen by his legs after climbing up a fence pole, and was "ripped to pieces" at the privately run Addo Croc and Lion Ranch near Port Elizabeth, 'The Sun' reported.
Veluchia Hassim, a tourist, said of seeing the beasts chewing on his carcass after being woken by screams at 5 AM on Sunday. She said: "We ran to the encampment. It was horrific. The one lion was gnawing on his ribs when we got there."
The wildlife resort's owner, Johnny Janse van Rensburg, had to shoot the animals dead so cops could recover the victim's remains.
A friend of Mr Bredenhand, Jamiel Jonas, said they had been partying all night. "After they braaied (barbecued) and partied at the ranch entrance, they came back home, but he wanted to play with the lions.
"Then just after 5 AM his friend came screaming for us to phone the police and for an ambulance. He was drunk. When we got to the camp we saw the remains of his body. Most of his stomach was torn out and his leg had been ripped off,"he said.
Police spokeswoman Gerda Swart said Bredenhand is believed to have been seized by the legs and dragged to his gruesome death.
She said: "He climbed the fence around their enclosure and clearly got too close. Since he was drunk he may not have been in sound mind, but it's an incredibly dangerous and stupid thing to do. People who play dangerous games with animals like lions are asking for trouble -- and he got it."