Martha is big, ugly, lazy and gassy. And a world champion.

In a competition annually dominated by the old, the tiny, and the hairless, the three-year-old Neapolitan Mastiff used her lollygagging youth to win the 29th annual World’s Ugliest Dog Contest.

She was a favourite of the Northern California crowd from the start, often plopping down on her side on stage with her droopy face spread across the ground when she was supposed to be showing off.

The judges didn’t even need to hear her signature snore to give her the award.

“Do you know you just won the World’s Ugliest Dog Contest?” asked Kerry Sanders of NBC News, one of three judges who gave Martha the crown.

Her handler Shirley Zindler answered for her: “I’d gloat, but I need a nap.”

Martha with her handler after her big win. Photo: AAP

Martha lumbered away with $US1,500 ($A1,975), a flashy trophy and a trip to New York for media appearances, all things she could hardly care less about.

The dog, from nearby Sebastopol, was rescued when  nearly blind from neglect by the Dogwood Animal Rescue Project in Sonoma County, where the contest was held.

After several surgeries, she can now see again, Zindler says.

The only animal in this year’s contest too big to be held by her handler, Martha beat out 13 other dogs, most of them the kind of older, smaller dogs who normally win.

Martha, who is three years old, smiles for the cameras. Photo: AAP

Moe, a 16-year-old Brussels Griffon-pug mix from Santa Rosa, California, who was the oldest in the competition, came in second.

He had lost his hearing and sight but his nose remains strong and he was enjoying all the smells at the Sonoma-Marin Fair where the contest is held, including funnel cakes and other fried goodies.

Chase, a 14-year-old Chinese Crested-Harke mix, came all the way from Neath, United Kingdom to take third place.

Sixteen-year-old Moe came in second place. Photo: AAP

The contestants were judged on first impressions, unusual attributes, personality and audience reaction.

Many of the contestants were adopted. Monkey, a six-year-old Brussels Griffon, and Icky, an eight-year-old unknown breed, were both rescued from the homes of hoarders.

These dogs – some with acne, others with tongues permanently sticking out – are used to getting called ugly. But for their owners, it was love at first sight.

“He’s my sexy boy,” Vicky Adler, of Davis, California, said of her eight-year-old Chinese Crested named Zoomer.

– AAP