Jack Ma (left), chairman of Alibaba Group and Pony Ma (right), chairman and CEO of Tencent Holdings Ltd at Fudan University in Shanghai, Nov 6, 2013. [Photo/IC]

"The slowdown in China's economy has worried Wall Street investors. The key manufacturing gauge, PMI, reading of 47.1 in August is the lowest since March 2009, almost close to the recession level. All of these have affected investor confidence on Chinese firms," she said.

The United States-listed companies from online search giant Baidu Inc to e-commerce players such as Alibaba and JD.com Inc have all announced plans to spend billions of dollars to repurchase their own shares in order to restore investor confidence.

However, as the dominant player in China's 2.8 trillion yuan ($439 billion) online retail market, Alibaba is expected to be the worst hit by the economic slowdown, said Lu Zhenwang, chief executive officer of Wanqing Consultancy in Shanghai.

"If there is no substantial increase in income, it would be very difficult for people to spend more online," he said.

Alibaba's report for the quarter ended June 30 has already shown signs of slowdown.

It showed that the company's total revenue reached $3.27 billion, up 28 percent year-on-year, which was much slower compared with the around 60 percent year-on-year growth in previous years.

"No Internet company can be a champion for two to five years. It's a tough business. Good thing is we have so many smart people. Bad thing is we have so many smart people competing with us," said Ma at the annual meeting of the New Champions 2015 of Summer Davos on Wednesday.

Shan Juan and Dai Tian in Dalian contributed to this story.