Even at a European conference about fintech, one country dominated the conversation: China.

This week, hundreds of fintech companies, from startups to tech giants, gathered at the Money 20/20 conference in Amsterdam, Netherlands. One key theme at the gathering was China's leading role in the fintech industry.

"Alibaba and Ant Financial, we are literally the world's largest fintech company, and we are the world's largest e-commerce company, and these two massive machines still, on an annual basis, grow at more than 50 percent a year," Li Wang, Alipay's head of EMEA, told CNBC's Arjun Kharpal at the conference.

Li said Alipay, a mobile and online payment platform, has 870 million active users, with 600 million in China and 270 million in the rest of the world. These user numbers are a testament to how quickly Chinese consumers have leapfrogged ahead of other countries when it comes to using fintech.