The situation is worse in impoverished areas such as Qingyang. Since women are reluctant to marry into families from poor villages, the groom's families have to pay a higher price for betrothal gifts, which means men from the poorest families are least likely to marry, said Zhang.

To keep a rein on soaring costs, the Qingyang government introduced a regulation against exorbitant betrothal gifts and extravagant wedding ceremonies last year, but the move proved a failure.

"The effect of the rule cannot reach our village because the tradition is too deep-rooted," said Zhang Hu.

"In the marriage market, men from poor families are in disadvantageous positions and have a weaker ability to bargain with women's families," said He Xuefeng, rural government researcher at Huazhong University of Science and Technology.

"To woo a potential spouse, men from poor families have to pay a higher price for betrothal gifts, which raises the cost of the marriage market, and other families have no choice but to follow suit. Thus a vicious circle is formed," said He.

The rising cost of marriage in rural areas has also led to other social problems.

Li Yanlin is a villager in Leping, East China's Jiangxi province. He bought a Vietnamese bride for his son for 45,000 yuan last year. However, his daughter-in-law disappeared only a few months later along with some other brides from Vietnam.

Asked why he would buy his son a bride, Li said the cost of a Chinese marriage is too much for his family.

In recent years, many women from neighboring Southeast Asian countries such as Myanmar and Vietnam have married rural Chinese men through marriage brokers or human traffickers. Marriage between such couples has become a prosperous business and one can easily find information about such foreign brides on online trading platforms.

But such illegal marriage is often fragile. Many foreign brides escape shortly after their wedding and domestic violence shadows the families as in the illegal relationships, husband and wife are unequal.

To help left-over bachelors find partners, local governments should develop their economies and improve the income of residents to encourage more women to marry local men, said Zhang Yi, adding that a rebalancing of China's sex ratio is also urgently needed.