政治合法性是政治学、社会学关注的核心问题。自社会学家韦伯系统地提出合法性概念以来,学术界对合法性的研究兴趣经久不衰，但国内相关实证研究甚少。本文以全国性调查数据和宏观统计数据为基础，选取了民众对政府的信任感为因变量，从经济绩效、价值认同、政治参与三个角度对政府信任感进行系统的实证分析，探讨政府合法性基础与机制。研究发现，经济绩效是民众对政府信任感的重要来源，相对于社会财富的增长，个体或家庭收入增长更能提升民众对政府的信任感。贫富差距扩大、官员腐败严重会显著地降低民众对政府的信任感，削弱政府合法性基础。非制度化的参与会导致政府信任感流失，而制度化的政治参与（选举行为）能在一定程度上带来更多的政府信任感。在实证研究基础上，文章进一步指出，政府转变发展方式，加大社会支出以及发展民主，这些并不仅是应然层面、理念层面的要求，更是巩固政府合法性基础的必然要求。

Political legitimacy is the core issue of political science and sociology. Since sociologist Max Weber systematically put forward the concept of legitimacy, academic circles have keep interest on this issue. However, relevant empirical research is rarely in China. In order to discuss the foundation and mechanism of the government legitimacy, this article selects the public trust to the government as the dependent variable, and does empirical analysis from the angles of economic performance, value identity, political participation, which based on national survey data and macroscopic statistical data. This study show that economic performance is the important source which can promote the public trust to government better, compared with the growth of society wealth, individual or family income. The widening gap between rich and poor, official corruption will significantly reduce the public trust in government, and weaken the government legitimacy foundation. Non-institutionalized participation will lead to the loss of government trust, and institutional political participation (election behavior) can bring more government trust to a certain extent. Based on empirical research, the article also points out that transformation development way, increase social spending and the development of democracy, are inevitable requirements to consolidate the legitimacy foundation of government, instead of the requirements in ideal level or concept level.