Hong Kong independence is the notion of Hong Kong as a sovereign state, independent from the People's Republic of China (PRC). Hong Kong is a special administrative region (SAR) of China and is thus granted a high degree of de jure autonomy, as stipulated by Article 2 of the Hong Kong Basic Law ratified under the Sino-British Joint Declaration. Since the handover of Hong Kong from the United Kingdom to the PRC in 1997, a growing number of Hongkongers have become concerned about what they see as Beijing's encroachment on the territory's freedoms and the failure of the Hong Kong government to deliver "genuine democracy". Advocating for Hong Kong independence became illegal after the Hong Kong national security law was enacted in 2020.

The current independence movement gained significant support after the 2014–15 Hong Kong electoral reform which deeply divided the territory, as it would have allowed Hongkongers to have universal suffrage conditional upon Beijing having the authority to screen prospective candidates for the Chief Executive of Hong Kong (CE), the head of the government of the territory. It sparked the 79-day massive occupation protests dubbed as the "Umbrella Revolution". After the protests, many new political groups advocating independence or self-determination were established, as they deemed the "One Country, Two Systems" principle to have failed.

According to a number of opinion polls conducted by the Chinese University of Hong Kong (CUHK), the Hong Kong Public Opinion Research Institute (HKPORI), and Reuters, a majority of Hongkongers do not support Hong Kong independence. However, support for independence is higher amongst young Hongkongers. In a CUHK survey of 1,010 Cantonese speaking Hong Kong residents in July 2016, nearly 40 per cent of respondents aged 15 to 24 supported the territory becoming an independent country, whereas 17.4 per cent of the respondents overall supported independence, despite only 3.6 per cent stating that they thought it was "possible". A majority of respondents, 69.6 per cent, supported maintaining "One Country, Two Systems", while slightly over 13 per cent of respondents supported direct governance by China.

Hong Kong Island was first occupied by British in 1841. The island was officially ceded as a crown colony to the United Kingdom from the Qing dynasty in 1842 after the First Opium War under the terms in the Treaty of Nanking. The other parts of Hong Kong, Kowloon and the New Territories were ceded permanently and leased for 99 years to the British in 1860 under the Convention of Peking and in 1898 under the Second Convention of Peking respectively. Although the Chinese government under the Kuomintang led by Chiang Kai-shek initially intended to take back the territory, the British resumed control of Hong Kong in 1945 after the Second World War, in which Hong Kong was occupied by Japan for three years and eight months. There were few advocates for decolonisation of Hong Kong from the British rule during the post-war period, notably Ma Man-fai and the Democratic Self-Government Party of Hong Kong in the 1960s but the fruitless movement ceased to exist without substantial support from the public.^{[citation needed]}

In the late 1970s and early 1980s, the question of Hong Kong sovereignty emerged on Hong Kong's political scene as the end of the New Territories lease was approaching. The British and Chinese governments had also begun negotiations in 1982 which would lead to the Sino-British Joint Declaration of 1984. Hong Kong and Macau were both removed from the United Nations list of non-self-governing territories, in which territories on the list would have the right to be independent, on 2 November 1972 by request of the People's Republic of China (PRC). Although there were advocates of Hong Kong independence, the majority of the Hong Kong population, many of whom were political, economic or war refugees from the Chinese Civil War and the communist regime in mainland China, wished to maintain the status quo.^{[citation needed]}

Of 998 Hongkongers polled by Survey Research Hong Kong Ltd. in March 1982, 95 per cent said that the status quo (i.e. British rule) was "acceptable", 64 per cent said the same about Hong Kong remaining under British administration but under Chinese sovereignty, 42 per cent about Hong Kong becoming a special economic zone of China, 37 per cent about independence, and 26 per cent about a handover to China without special provisions. When asked for their preferred outcome after the 1997 deadline stipulated by the Sino-British Joint Declaration, 85 per cent of respondents supported the continuation of British rule – 70 per cent supported the status quo, while 15 per cent supported the transformation of Hong Kong into a British trust territory. Only 4 per cent of respondents supported full Chinese sovereignty over Hong Kong, while 2 per cent answered "None of the above" (including those who supported independence).

The request for a Hong Kong representative in the Sino-British negotiation was rejected by Beijing. In 1984, the British and Chinese governments signed the Sino-British Joint Declaration which stated that the sovereignty of Hong Kong should be transferred to the PRC on 1 July 1997, and Hong Kong should enjoy a "high degree of autonomy" under the "One Country, Two Systems" principle.^{[citation needed]}

From 1983 to 1997, Hong Kong saw an exodus of emigrants to overseas countries, especially in the wake of the 1989 Tiananmen Square protests and massacre, when more than a million Hongkongers showed up on the streets to support student protesters in Beijing. The Tiananmen massacre of 1989 strengthened anti-Beijing sentiments and also led to the emergence of the local democracy movement, which demanded a faster pace of democratisation before and after 1997.^{[citation needed]}