Liang Qichao believes that "saving the nation from extinction" is the starting point of reform and reform, and "reform and reform" is the only way to save the nation from extinction and survive. First of all, from the viewpoint of bourgeois evolution theory, he commented that "political reform" is in line with the law of development of things. Secondly, he refuted the fallacy that the die-hards in the Qing dynasty ruling group insisted on "the law of ancestors cannot be changed" with concrete facts. It shows that it is an ancient and modern axiom that the law changes at any time, and the legal system cannot be "once and for all". Finally, he analyzed the current situation in China at that time and pointed out that "it is impossible to survive without political reform". Liang Qichao believes that China must reform China's politics, law, culture, education system and even the country's political system if it wants to "save the country" and "strengthen itself" and implement political reform. First of all, political reform "must first change people." Secondly, reform "must promote civil rights." Third, political reform must transform an authoritarian regime into a constitutional regime. The specific methods are as follows: First, establish an elected parliament. Second, make a constitution. Third, implement "separation of powers". Liang Qichao learned from the principle of "separation of powers" advocated by the western bourgeoisie, and combined with the situation in China, established his own theory of separation of powers, that is, Congress exercises legislative power, the Minister of State exercises administrative power, and the independent judicial department exercises judicial power. Moreover, he called the unification of the sovereignty of the three powers "body" and the exercise of the three powers "use", that is, the so-called "body of the three powers, according to the monarch". In other words, the "body" of constitutional monarchy and autocratic monarchy is exactly the same, and the "monarch" in constitutional monarchy and autocratic monarchy enjoys the highest power. The difference lies in "use", that is, constitutionalism has some restrictions on the use of the three powers. Liang Qichao insisted on the relationship between the rule of law and the rule of man. First of all, he opposed the idea that only the people can rule. He thinks that the rule of man has many disadvantages: (1) the rule of man has a short time and a small scope, and "the death of a person leads to political interests", while the rule of law has a long time and a wide scope. (2) The rule of man is a kind of sage politics. There are fewer wise kings in the world than bad kings, so there is no long-term stability in the world. (3) From the reality of China, it is not feasible to rely solely on the rule of man, because the country is large and the government affairs are complicated. Secondly, he also opposes relying solely on the rule of law. He thinks: (1) people can make laws, and illegal people can control them. Laws should be made by people. Only people with certain morality and wisdom can make good laws and then have good governance. (2) "I can't do things by myself." Good law leads to good governance. Only when people use good law properly can good law play its role. In addition, Liang Qichao also emphasized that "law cannot be independent". In his view, morality has social sanctions and law has national sanctions, and the two should be used together. To sum up, Liang Qichao has rich legal thoughts and plays an important role in the development of modern ideological history.