The contest is held annually in Petaluma, California as part of the Sonoma-Marin Fair and has garnered tremendous media attention.
First established in the 1970s, organizers say it is bound to “celebrate the imperfections that make all dogs special and unique”.
It now draws an audience of up to 30,000, with the winner receiving $1,600, a trophy and a free trip to New York.
At the 2022 edition, Mr Happy, a 17-year-old Chinese Crested and Chihuahua mix from Arizona, won the award.
And there have been plenty of entries so ugly they’re adorable over the years.
Here are 19 of the dogs with faces only a mother could love.
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