The Three Principles of the People, also known as the San-min Doctrine, is a political philosophy developed by Sun Yat-sen to make China as a free, prosperous and powerful nation. At the time of Sun, China was governed as an Empire under the Qing dynasty, which was made up of Manchu people. Ordinary Chinese, the Han, were not part of the government. Sun's main goal was to end the Qing government and replace it with a Chinese-ruled republic with freedom and justice for all. He also wanted to limit the power of foreign powers in China, which had become great under the Qing, including foreign quarters in Chinese cities, and foreign (European) armies being stationed there. The three principles were Sun's idea of how to end Manchu rule and create a modern, independent and free China.

The three principles are often summarized as nationalism, democracy and the people's well-being (sometimes translated as socialism, although there are differences to the socialism of Karl Marx).

The influence of the three principles of the people stay in the government of the Republic of China, which currently administers Taiwan. This philosophy influenced also the modern Communist Party of China and the Chinese Socialism. Sun is praised in both states as a great statesman and philosopher.