Investors attending the Hong Kong-Shanghai stock connect program should firstly understand and accept each other's market rule, said China's chief securities regulator.

"The Hong Kong-Shanghai stock connect is an innovation based on linkage of the bourses in Shanghai and Hong Kong, based on the condition that it will not change the trading rules and habits of investors in both markets," said Xiao Gang, chairman of the China Securities Regulatory Commission during his speech on the Asian Financial Reform held in Hong Kong on Monday morning.

International investors may find it hard to adapt to the Chinese market, because rules are different. For example, we have daily limit for share price growth, as well as pre-trading check requirement. It takes time for overseas investors to understand and fit in, he said.

Analysts in Hong Kong said Xiao's remark may indicate that the mainland authority is unwilling to adjust the market rules according to overseas investors' claim.

Xiao's remark came two month after the stock connect program kicked off. Trade volume has been lagging off people's expectation, as many overseas investors, especially big mutual funds, said there are compliance issues that block the way. For example, Chinese regulations compel international investors to deliver securities to their broker before 7:45 am in Hong Kong on the day they plan to sell the shares on the mainland. Many asset managers have compliance rules that prevent them from transferring equities before they have sold the securities.

Only one fund under the Luxemburg supervision has been given permission to take part in the stock connect program by mid January, according to Bloomberg. Luxumburg is home to equity funds with assets worth about $1.2 trillion.

"The trade system went fairly smooth in the firs two months, and we will do more to improve the system," Xiao said.