Calling the connect's launch "imminent," Li told CNBC that he was upbeat about the link despite revenue from the existing Shanghai-Hong Kong Stock Connect program falling 38 percent on-year to 71 million Hong Kong dollars ($9.2 million) in the six months to June 30.
Hong Kong's Securities and Futures Commission and the China Securities Regulatory Commission launched the Shanghai-Hong Kong Connect in 2014. The link, hailed as a major step in China's efforts to open up its capital market, allows foreign investors to place buy or sell orders for Shanghai's A-share market through brokers in Hong Kong. Chinese investors, meanwhile, are be able to use mainland brokers to invest in Hong Kong's H-share market.
The Shenzhen-Hong Kong connect would open up mainland China's second-largest stock exchange in the same way.
Li said the link was vital to bringing more tradeable products to a wider marketplace in the future.
"Over time, we are hoping that we are able to bring more truly international products, international listings and international companies, or international risk management instruments, for Chinese investors to buy, because that's the last residual pool of capital in the world today that has yet globally deployed," Li said.
China's securities regulator recently set up a special working group tasked with launching the Shenzhen-Hong Kong Stock Connect scheme, Chinese financial magazine Caixin reported on Thursday.
This followed comments in March by Chinese premier Li Keqiang that the this year.
In its half-yearly report, released on Wednesday, the HKEx reported a 27 percent on-year decline in net profit to 3 billion Hong Kong dollars, and said that average daily turnover almost halved in the period to HK$67.5 billion.
In a presentation to investors, the bourse attributed its weaker performance to bearish investor sentiment and subdued cash market trading activity globally.
"This year is going to be overall challenging almost for everybody," Li told CNBC.