Mr de Beer, from Hamilton, said he was proud of his girlfriend, adding: "She definitely deserves it, she's a princess anyway so she deserves to wear a crown."
In second place was Sarah Halvorson, a police officer from Whangarei. Miss Halvorson, 20, said she had entered for a shot at the prize money and for fun.
"I'm a cop so I thought it was funny just to go out there in the first place."
Third was Talitha Barton from Te Puke, who said she had entered for a confidence boost.
Mr de Beer said he had not intended on competing but when he heard the ZM hosts say there were no other entrants, he decided to give it a go.
The Mr Mount winner was Colin Francis and third place was Nathan Harris.
Radio Network solutions development manager Sarah Catran said this year's Miss Mount had been one of the best ever.
"Our stage manager has been to every competition and he said this was one of the best he had seen in years.
"It was the most contestants we'd had in years and the first time we had run the men's competition."
Miss Catran said the crowd had really got into the spirit of the event.
"There was good crowd participation from groups of people. I think the contestants must have brought in groups of supporters to cheer them on.
"It was one of the biggest crowds I've seen here."
Miss Catran said there had been a lot of men who had pre-registered for the inaugural Mr Mount competition, but none had shown up on the day.
As a result, the organisers asked men in the crowd to take part. She said many local sponsors helped with the event.
