the ideological basis of the political program of the Chinese Nationalist leader Sun Yat-sen (1866–1925), championing the principles of nationalism, democracy, and socialism.

The principles were originally formulated as slogans for Sun's revolutionary student group, the United League, one of the chief forces behind the 1911 Republican Revolution, which ended the Qing dynasty rule of China. After the failure of this revolution to establish democracy in China, Sun formed a new party, the Nationalist Party (Kuomintang), utilizing his principles as fundamental doctrine. In 1922 the Nationalists formed an alliance with the Chinese Communist Party. Beginning the following winter, Sun, in response to communist demands for a more formal party ideology, gave a series of lectures in which he sharpened and defined his three principles.

The first principle, minzu zhuyi, or “nationalism,” earlier had meant opposition to the Qing (Manchu) dynasty (Qing dynasty) and to foreign imperialism; now Sun explained the phrase as denoting self-determination for the Chinese people as a whole and also for the minority groups within China. The second principle, minquan, or the “rights of the people,” sometimes translated as “democracy,” could be achieved, Sun explained, by allowing the Chinese people to control their own government through such devices as election, initiative, referendum, and recall. The last principle was minsheng, or “people's livelihood,” which is often translated as “socialism.” This was the most vague of the three principles, but by it Sun seemed to have in mind the idea of equalization of land ownership through a just system of taxation.

After the Nationalist-communist split in 1927, both Mao Zedong and Chiang Kai-shek (Jiang Jieshi) claimed to be carrying on the true spirit of the Three Principles of the People.