Bank of China (BOC) issues five denominations of banknotes for use in Hong Kong; it is one of three banks to do so. (The others are HSBC and SCB.) BOC paper money comes in HK$20, $50, $100, $500, and $1000 notes, just as they do from the other banks. (A polymer $10 note comes from the HK government.)
Bank of China in its current form has only existed since 2001, being a merging of several Chinese subsidiaries. As an official banknote issuer, BOC follows the standardized coloring system on its notes. The most recent series came in 2010, and each note shows a different site in Hong Kong. The famous Bank of China building, arguably the most noticeable building in the famous Hong Kong skyline, also appears on each note. The BOC 1994 series included five notes from $20 to $1000; a new $1000 note came in 2001 and an entire new series in 2003 and 2010. (A special $20 was also issued in 2008 by Bank of China.)
See also: Nagorno-Karabakh rare banknotes and collectible paper money
Collecting Bank of China banknotes means only going back to 1994, when the bank was first authorized to issue them. In contrast to HSBC and SCB, BOC notes appeal to collectors who like more recent items. Although there may generally be fewer BOC banknotes for sale at any given time, there are constantly new additions to online sales listings. Completists and other types of HK banknote collectors should watch the listings closely.
