Relations between the government of Hong Kong and the Republic of China (Taiwan) encompass both when the Republic of China controlled mainland China, and afterwards, when the Republic of China fled to Taiwan.

The National Day of the Republic of China, also referred to as Double Ten Day or Double Tenth Day, is a public holiday on 10 October, now held annually as national day in the Republic of China. It commemorates the start of the Wuchang Uprising on 10 October 1911 which ultimately led to the collapse of the imperial Qing dynasty, ending 2,133 years of imperial rule of China since the Qin dynasty and establishment of the Republic of China on 1 January 1912. The day was once held as public holiday in mainland China during the Mainland Period of the ROC before 1949. The subsequent People's Republic of China continues to observe the Anniversary of the Xinhai Revolution at the same date but not as a public holiday, which put more emphasis on its revolutionary characteristics as commemoration of a historical event rather than celebration to the founding of the Republic of China.