Sun Yat-sen was the first to thoroughly oppose feudalism, organize revolutionary political parties, launch an armed uprising, led the Revolution of 1911 which shocked China and foreign countries, overthrew the autocratic rule of the feudal dynasty that lasted for thousands of years in China history, opened a new chapter in the history of China's democratic revolution, and made great contributions to later generations. The obvious differences between Sun Yat-sen and the hero of peasant uprising who resisted the feudal dynasty and the contemporary representative of bourgeois reformists are as follows: First, he combined the essence of capitalist system in Europe and America with the backward feudal autocracy in China through other ways, and from the purpose of "people-oriented", he not only put forward the basic theory of "Three People's Principles", but also made great efforts to transform backward old China from the aspects of national system, politics, economy and culture. Second, from the beginning of initiating and organizing the revolution to the end of his life, in the process of leading the whole bourgeois democratic revolution, facing the call of the Manchu court, the siege of reactionary warlords, the intimidation of imperial power, the controversy of reformist royalists, the rebellion within the camp and the differences among comrades in the party, he unswervingly adhered to the thorough anti-feudal stance and firm revolutionary direction, organized and reformed revolutionary political parties and launched revolutions many times in extremely difficult and risky environment. Third, he has always adhered to the lofty spiritual realm of "serving the public wholeheartedly", from establishing the association and the League, launching ten armed uprisings in Guang, Hui and Huang Huagang, to leading the Revolution of 1911, establishing the provisional government, holding the second revolution, organizing and reforming the Kuomintang, establishing the Whampoa Military Academy, cooperating with the implementing country, and giving up personal fame and fortune, showing broad-minded and selfless spirit. Sun Yat-sen's theory, position, belief and moral sentiment can be said to be unique. It is precisely because of Sun Yat-sen's unremitting efforts and the popularization of revolutionary theory that the broad masses of people in China got rid of the shackles of feudal thought and the misunderstanding of democratic "reactionary" political thought, which effectively promoted the development of the democratic revolutionary movement in China, expanded its influence and made democracy deeply rooted in the hearts of the people. Even the later "New Democratic Revolutionary Movement" was developed on the basis of Sun Yat-sen's work.