A Sydney man who claimed he was publicly ridiculed because of his mullet has suffered a setback in his defamation case against media organisations.

Ziggy Mosslmani was photographed at an 18th birthday party in Sydney in July last year by a professional photographer who then uploaded the photo to Facebook.

Within days the post went viral, spurring satirical memes and media stories about his haircut.

Mr Mosslmani claims he was ridiculed for his mullet after members of the public created photoshopped images of him and news organisations published the photos with headlines he claimed made him out to be ridiculous, ugly and a joke.

One article suggested his mullet hairdo belonged in the "Hairy Hall of Shame".

The original photo has been shared hundreds of times on Facebook and there are nearly 2,000 comments on the picture, while stories about the photo have been viewed more than 1.7 million times.

Plaintiff's 'striking' mullet fuelled internet interest: judge

District Court judge Judith Gibson struck out the teenager's imputations of ridicule and asked him to file an amended statement of claim.

In handing down her decision, Judge Gibson said most of the comments were humorous in nature.

"The plaintiff's striking mullet haircut has generated a great deal of interest on the internet, most of it humorous, and some of it in the form of clever observations, such as the 'Pythagoras' direction in one of the memes," she said.

The photographer, Jeremy Nool, said he had no idea the photo would make such an impact.

"It was one of the photos where everyone's dancing. I thought this is a good angle and the lighting was good," he said.

"When I put it up I didn't expect anything to happen, but it blew up and went viral."