Bank of China Limited (BOC) was officially listed on the main board of the Hong Kong Exchange and Clearing Limited (HKEx) and the trading of the bank's H share began on Thursday.

BOC is the second listed bank among the four biggest commercial banks in the Chinese mainland and the bank's initial public offering is the world's biggest of the kind in six years.

The debut share price was 3.15 HK dollars, 6.8 percent up over the initial public offering (IPO) price of 2.95 HK dollars.

BOC Chairman Xiao Gang said at the bank's listing ceremony at the HKEx that the BOC's IPO is one of the most successful IPO programs in the international capital market, which indicated the international investors' confidence in China's long-term economic prosperity and acceptance of the bank's century-old brand.

The BOC offered a total of 25.57 billion H shares in its global offering, including initially 1.28 billion H shares for the Hong Kong public offering and 24.29 billion H shares for the international offering, subject to adjustment if there is substantial oversubscription in the Hong Kong public offering.