Chinese Huayan and Tiantai Buddhist School are the most philosophical schools of Chinese Buddhist Schools,which had a great influence on the character of Chinese Buddhism.Through the criticism of Huayan Buddhist School,especially of the thought of Chengguan and Zongmi,Fengtan attempted to harmonize differences in teachings of Huayan and Tiantai Buddhist School.There are some biased comments on Chengguan and Zongmi,Fengtan observantly pointed out the transformation from "Emptiness of Dharma-nature" to "Dependent Origination of True Mind" of the ideological foundation of Chinese Huayan Buddhist School.Fengtan also marked that there are some connections between Fazang’ Huayan thought and Zhiyi’s Tiantai thought.All of these will be helpful to correctly understand the theoretical characteristics of Chinese Huayan Buddhist School and Tiantai Buddhist School.