An Australian street performer has set a new Guinness World Record by swallowing 18 swords at the same time.

Chayne Hultgren, aka The Space Cowboy, swallowed the blades, each of which was 72 centimetres long, in Sydney this morning.

The 31-year-old from Byron Bay said he was thrilled to have made history.

"It's amazing," he said. "I've been preparing for this since I was 16."

Hultgren beat his own previous record of 17 swords - also a Guinness World Record - which he set in 2008.

Hultgren began practising the art of sword swallowing at the age of 16 when he swallowed his first hose.

A few years later he upped the ante and began using stainless steel blades.

He swears his latest feat is not dangerous, but the cheeky entertainer conceded that "it wasn't recommended by my doctor".

"It's educated risk," he said.

"I don't just straight away grab 18 blades and shove them down my throat - you've got to practise a lot and build up to it.

"So I stretch my throat with hoses and use a few different techniques to basically enable me to do what, until now, has been impossible."

He is the only person in the world to down more than 13 blades simultaneously, he said.

- AAP