The American naturalist who decided to film himself being swallowed alive by a giant snake has survived ... and so has the anaconda.

Paul Rosolie wanted the spotlight turned on the destruction of the Amazon rainforest and dreamed up the stunt guaranteed to get attention.

Anacondas are the largest snakes in the world and typically suffocate their prey before ingesting it, making Rosolie's attempt all the more dangerous.

He's not telling people how he did it ahead of the screening of his Discovery Channel documentary Eaten Alive.

But he did have a specially-designed carbon fibre suit, equipped with a breathing system.