HKEX is a world-leading capital raising venue for Hong Kong, Mainland Chinese and international issuers. As of 2019, the Hong Kong Exchange has 2 449 listed companies with a combined market capitalization of HK$38.2 trillion. The five largest companies by market capitalisation include Alibaba Group Holding Ltd. – SW; Tencent Holdings Ltd.; China Construction Bank Corporation – H Shares; China Mobile Ltd. and HSBC Holdings plc. Additionally, the exchange services 12 795 listed securities, among which it is possible to find interest rate and cross currency swaps, real estate investment trusts, forex and commodities derivatives and other instruments. Uniquely positioned at the intersection of Chinese and international capital flows, Hong Kong has long been Connecting China with the World. With the accelerated opening-up of China's capital markets. What is more, Hong Kong ranks as the number 1 Global IPO formation centre in five of the past eight years. Additionally, the Hong Kong Futures Exchange enables a multi asset class derivatives exchange that saw 263 million contracts being traded in 2019.

The exchange first introduced a computer-assisted trading system on 2 April 1986. In 1993 the exchange launched the "Automatic Order Matching and Execution System" (AMS), which was replaced by the third generation system (AMS/3) in October 2000. Subsequently, On 7 March 2011, the exchange extended its hours in the first of two phases. The morning session now ran from 9:30 am to 12:00 noon, followed by a ninety-minute lunch break, and an afternoon session from 1:30 pm to 4:00 pm. Index futures and options now began trading at 9:15 am, thirty minutes earlier than before, and closed at the same time as before, 4:15 pm. On 5 March 2012, the lunch break was cut to sixty minutes, with the afternoon session running from 1:00 pm to 4:00 pm.

It is perfectly normal for Hong Kong stocks of even well-known companies to trade at prices that correspond to less than HK$4 a share. A Hong Kong stock would not be considered a penny stock unless its price was less than about HK$0.50. Additionally, each stock has its own individual board lot size (an online broker will usually display this along with the stock price when you get a quote); purchases in amounts which are not multiples of the board lot size are done in a separate "odd lot market". Finally, there is a close-in-price rule for limit orders, which must be within 24 ticks of the current price. Individual brokers may impose an even stricter rule; for instance, HSBC requires limit orders to be within 10 ticks of the current price. Broker support for triggered order types such as market-if-touched orders would allow placing orders further away, which would be sent to the exchange when the price condition was established.

The Securities and Futures Commission (SFC) is an independent statutory body responsible for regulating the market, safeguarding market integrity, and enforcing securities and futures market legislation. Parties regulated by the SFC include HKEX and its subsidiaries (including the stock and futures exchanges and associated clearing houses), financial market intermediaries (namely securities dealers which include Exchange Participants; sponsors; share registrars; fund managers; and investment advisers) and investors.

The SFC's statutory regulatory objectives are:

• to maintain and promote the fairness, efficiency, competitiveness, transparency and orderliness of the securities and futures industry;
  
• to promote understanding by the public of the operation and functioning of the securities and futures industry;
  
• to provide protection for members of the public investing in or holding financial products;
  
• to minimise crime and misconduct in the securities and futures industry;
  
• to reduce systemic risks in the securities and futures industry; and
• to assist the Financial Secretary in maintaining the financial stability of Hong Kong by taking appropriate steps in relation to the securities and futures industry.
  

All companies seeking a primary listing in Hong Kong, regardless of their place of incorporation, are subject to the Listing Rules, the SFC's Codes on Takeovers and Mergers and Share Repurchases and other applicable regulations. The Listing Rules apply as much to overseas companies listed in Hong Kong as they do to companies incorporated and listed in Hong Kong. The overseas companies may also be subject to additional requirements, modifications or exceptions set out in the Listing Rules.