Yan Fu is a famous enlightenment thinker in Modern China and his translated works of western philosophy and social sciences have exerted a far-reaching influence on China's ideological circles. He is a master of ancient Chinese civilization, which enables him to criticize it from the perspective of the theory of evolution. In his opinion, Chinese political ideology, with its particular "preference of the remote to the present", lacks genuine politics and tends to mix politics with ethnics. Taking the actual effect into consideration, he preferred "rule of law" advocated by the Legalists to "rule of morals" embraced by the Confucianists. However, he approved of Confucian positive attitude towards social life and in his old age, prized Confucian values as the essential of the nation. He believed that the essentiality of ancient Chinese civilization and the newness of western learning should be complimentary with each other and the national essentiality would stay. In recent years, how to evaluate the traditional culture has become a new academic problem and Yan Fu's comments tell us much.