Yao, 23, claimed 137,610 votes in a global poll, the website of the contest announced. She was also named the Perfect Figure.
2008 Miss Asia champion Eunis Yao is flanked by the runner-up Belinda Yan (left) and third place-getter Lene Lai at the finals of the 2008 Miss Asia pageant in Hong Kong on Dec. 7, 2008.
Twenty-two year old Belinda Yan, who is also from Hong Kong, received 129,416 votes to be named runner-up and Miss Photogenic. Taiwan's 19-year-old Lene Lai was awarded third place with 60,542 votes.
The top three were selected by fans worldwide who voted for their favorite by either sending text messages or voting via the event's website.
Previously, winners were decided by a panel of judges.
This year's contest also attracted candidates from the Chinese mainland, as well as Japan, Singapore, South Korea, Thailand and Turkmenistan.
The Miss Asia pageant was launched by Asia Television Limited, a Hong Kong-based broadcaster, in 1985. Previous champions include Kristy Yang (in 1995), who went on to become a popular actress, and Nina Li (in 1986), wife of action star Jet Li.