The Three Principles of the People is a political philosophy developed by Sun Yat-sen as part of a philosophy to improve China made during the Republican Era. The three principles are often translated into and summarized as nationalism, democracy, and the livelihood of the people. This philosophy has been claimed as the cornerstone of the nation's policy as carried by the Kuomintang; the principles also appear in the first line of the national anthem of the Republic of China.

Sun Yat-sen, better known in China as Sūn Zhōngshān, was a Chinese revolutionary statesman, physician, and political philosopher who served as the first provisional president of the Republic of China and the first leader of the Kuomintang. He is called the "Father of the Nation" in the present-day Republic of China (Taiwan) and the "Forerunner of the Revolution" in the People's Republic of China for his instrumental role in the overthrowing of the Qing dynasty during the 1911 Revolution. Sun is unique among 20th-century Chinese leaders for being widely revered by both the Communist Party in Mainland China and the Kuomintang in Taiwan.