Kathy Xu is founder of Shanghai's Capital Today Group. [Photo/Bloomberg]

The largest venture capital fund ever raised by a woman isn't in Silicon Valley or even the United States. It's in Beijing and is run by a former librarian who keeps such a low profile that she's a mystery in China.

Chen Xiaohong rarely attends industry conferences or events. She hadn't given a media interview in more than a decade until agreeing to break her silence this summer. "I don't like being part of a club," said Chen during a four-hour discussion at her firm's headquarters. "I believe in staying independent, making your own decisions."

Chen, 46, is part of an unusual group of female investors who have risen to the top of the venture business in China and helped fuel the country's technology boom. They've backed some of China's most successful startups and their influence is growing as they raise more money, recruit other women and seed the next generation of technology companies.

Chen and her peers have become part of the mainstream in China in a way that's proven elusive in the United States. US venture firms have faced accusations of sexism and discrimination for years, including in an unsuccessful lawsuit filed by a female partner against storied Kleiner Perkins Caufield & Byers. Despite the criticism, the firms have made little progress in promoting women. Among the top US venture firms, women make up about 10 percent of the investing partners and only half of the firms have any women of that rank. China is already more balanced: About 17 percent of investing partners are female and 80 percent have at least one woman.

An increasing number, like Chen, lead their firms. Kathy Xu is founder of Shanghai's Capital Today Group, which has $1.2 billion under management and was an early backer of the e-commerce company JD.com Inc. Anna Fang is CEO of ZhenFund, one of the most influential angel investors in China. Ruby Lu, Chen's partner at her firm H Capital until this month, previously co-founded the China business for DCM Ventures.

Their success is bringing more women into China's technology industry. The Chinese government estimates females found 55 percent of new internet companies and more than a quarter of all entrepreneurs are women. In the US, only 22 percent of startups have one or more women on their founding teams, according to research by Vivek Wadhwa and Farai Chideya for their book Innovating Women: The Changing Face of Technology.

China has quietly become one of the best places in the world for women venture capitalists and entrepreneurs. Chen raised a new $500 million fund, the biggest ever by a woman, according to Preqin, and increased her assets under management to about $1 billion. The largest women-led fund in the US was about half that size, according to Preqin's data.