A 26-year-old man from Lismore in New South Wales has provisionally set a new world record for the lowest score in a round of golf.

Little-known Australian professional Rhein Gibson fired a 16-under-par 55 at the River Oaks Golf Club in Oklahoma.

Only one other player has ever shot a 55 before - Homero Blancas, a PGA Tour player from the 1960s, managed the feat on a par-70 course of just 5,000 yards.

But that score was taken out of the record books after harder qualifying rules were set.

Gibson's round falls in line with the new rules and is set to become a new world mark once it is cleared.

Starting on the back nine of the 6,698-yard par-71 course, Gibson started with a routine par before notching up two eagles and a birdie in his next three holes.

He then continued his birdie blitz with five straight to close out a mind-boggling nine holes in 26 shots, 10-under-par.

Forced to wait 15 minutes at the turn, Gibson could only manage pars on the first two holes but then birdied six of the last seven to post an incredible 55.

"I just kind of got hot I guess and every putt I hit went in, that's the best I can explain it to be honest," Gibson said.

As he faced an eight-foot birdie putt on his final hole, Gibson knew history was in the offing but felt calm.

"I wasn't nervous," he said.

"I had this song playing in my head. It is that new one from the Eli Young Band. It was in there all day."

He says it is hard to believe he's posted a score unmatched by some of the game's greats.

"It's really only starting to sink in now," he said.

Gibson is aspiring to join the PGA Tour, playing the smaller Golfweek National Pro Tour, and through six events is 12th on the money list.

ABC/AAP