The contents and form of Taoism had very full of substance and development in Dong Jin and South Dynasty. Taoism had become a religion of complete meaning during this period. Ger Hong、Lu Xiujing and Tao Hung-ching were great masters who had contributed to Taoism in this very important time. Ger Hong established more scholarly theory for Taoism, and he was a comprehensive expression of celestial thought. Lu Xiujing set up dispensation and ceremony for the sake of restraining Taoist believers. Besides and strengthening Taoist organization. Lu Xiujing arranged Taoist scripture and edited the first catalogue of Taoist scripture. Tao Hung-ching made up celestial pedigree,established the initiation of Taoist groups and stood for the religious teachings that blended Confucianism, Buddhism and Taoism. The three outstanding great Taoist masters are worth being put on the same platform to investigate. This study compares the three great masters from aspects such as their experiences, learning, manners of spiritual cultivation, Buddhist thinking inclusion and the relation with politics. This study points out that there are similar common features in the three great masters. Furthermore, as regarding the characteristics of the three great masters, Ger Hong is celestial Taoist, Lu Xiujing is Confucian Taoist, and Tao Hung-ching is Political Taoist.