Small investors not protected: ex-official

China's securities regulator has failed to protect the interests of small and medium-sized investors as the country's stock market has languished over the past decade, a former securities official said over the weekend.

The domestic stock market's performance should be in accordance with China's economic growth, so the index should have grown steadily, Zhou Zhengqing, former chairman of the China Securities Regulatory Commission (CSRC), said at an investors' conference held in Beijing Saturday.

However, the mainland stock market has plummeted by 65 percent since the global financial crisis broke out in 2008, in contrast to the US stock market, which has only fallen by 8 percent during the same period, according to Zhou.

"I earned money in 2007 when the benchmark Shanghai Composite Index hit its record level of over 6,000 points. But gone are the good days and now my investment has shrunk by one-third," Wang Hui, a veteran retail investor in Wuhu, East China's Anhui Province, told the Global Times Sunday.

"Buying a house or saving the money in a bank would be a better choice than investing in the stock market," he said.

Zhou said the cause of China's sluggish stock market lies in the poor quality of listed companies. He cited the US as a good example, where about 6 percent of publicly traded firms are delisted from the New York Stock Exchange every year, and 8 percent from NASDAQ.

China should improve the delisting mechanism to eliminate underperforming firms, as a means to increase investors' returns on investment and protect their interests, Zhou said.

A risk warning board, mainly used as a trading platform for stocks preparing for delisting or relisting, was officially launched on the Shanghai Stock Exchange Friday, as part of the CSRC's efforts to promote delisting reform.