Nearly 7,500 women from Hong Kong married Chinese men in 2013, a threefold increase from 2003. The number of cross-border marriages registered in Hong Kong accounted for 38 per cent of the total in 2013, compared with 32 per cent 10 years earlier.
It is not hard to understand why women look for love outside of Hong Kong, say marriage brokers and sociologists. Hong Kong is a tough marriage market for women because of the city's skewed gender ratio — 876 males for every 1,000 females, a gap predicted to worsen to 712 to 1,000 by 2041.
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"Men are in a short supply," says Paul Yip, an expert on population policy at the University of Hong Kong. "And men always like to marry down, women always like to marry up . . . what we will see is an increasing number of women who remain single."
China's economic boom — and with it, its growing number of wealthy men — has also encouraged women to consider partners from the mainland.
Renowned for being independent and selective,, says Sandy To, a sociologist at the University of Hong Kong, women from the territory tend to favour Chinese bachelors with decent education, particularly haigui or "sea turtles" — Chinese who have studied overseas and returned to China.
More than 400,000 haigui returned to the motherland last year, according to Chinese government data. "They speak fluent English, have the global perspective and cultural sophistication," she says. "Their background is similar to that of professional Hong Kong women. They would click."
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There could be a political and social benefit to these marriages. Tensions between Hong Kong, anxious to maintain its status as an international metropolis, and mainland China have risen in recent years, most noticeably with last year's pro-democracy protests.
Such cross-border liaisons are believed to help defuse conflicts and enhance mutual understanding between two sides. "Of course, this [cross-border marriage] brings us closer, says Mr Yip. "What else could happen? They can influence us and we influence them too. We don't need to be paranoid about this."
But, Mei Ling Liu, founder of Hong Kong Matchmaker, an elite dating agency, voices a note of caution. Although China and Hong Kong are geographically close, she warns that "the core values and social mentality are different".
Some cultural differences may be difficult to overcome. The government data, though comprehensive, do not include divorces of cross-border couples.
"Hong Kong people speak terrible Mandarin and (most) Chinese speak terrible Cantonese," Ms Mei says. "When you talk about business, you can struggle and manage. When you talk about love, you really need to communicate."
"We don't have a big problem in our daily communication," says Ms Cheung of her relationship. But her accent still marks her out as a Hong Kong native. "He (my husband) sometimes makes fun of me."