"I have no words," she said when asked to describe how she felt. "I am really happy."
The 23-year-old administrative clerk from the British territory on the tip of the Iberian peninsula was a crowd favorite after winning the swimsuit competition.
She joined seven other contestants in the final round of the show. The loudest cheers were reserved for Miss South Africa, Tatum Keshwar who was the second runner-up.
First runner-up was Miss Mexico, Perla Beltran Acosta.
Aldorino did not give an indication of what her immediate plans were now that she had won the prestigious title.
"I will try to do the best that I can now that I have opportunity and advantage," she said in a brief interview with The Associated Press after the event.
Gibraltar, known as The Rock, is a quirky, multicultural British outpost of 30,000 people, most of whom speak perfect Spanish and even own property along Spain's southern Mediterranean coast. An estimated 12,000 people cross over from Spain daily to work and many more to visit.
Spain ceded sovereignty of Gibraltar to Britain in a 1713 treaty, but has persistently sought its return, claiming the territory as a natural and historic part of its geography. The outcropping is in the Strait of Gibraltar, for centuries a strategic waterway linking the Atlantic and the Mediterranean.
Wearing her crown of tiny jeweled blue flowers, Aldorino said had been impressed with South Africa, which was hosting its seventh Miss World final.
"It has a lot to offer," she said.
South Africa is taking advantage of the world's attention as the country gears up to host the World Cup in June.
Saturday's show, which was televised across the world, gave a taste of South Africa's rich cultural heritage and natural attractions.
The 112 contestants were welcomed at the start by Zulu dancers and the ululating African female performers. There were clips from the finalists time in South Africa -- showing the beauties cuddling cheetahs and lions, on pristine white beaches and even playing soccer.
"It is a wonderful opportunity for South Africa to showcase that they can host a world-class event and also a great tourist opportunity to show off the best that South Africa has in store," Keshwar said.