Chen tuan conforming to the mainly thought of religious integration by the late Tang Dynasty, after actively absorbing and assimilating of Confucianism, Buddhism, and Taoism of mind-nature, preliminarily constructs to inner alchemy as the main content, the thought of religious integration as mainly characteristics of the "yi-ology" and the new system of practice, which generally laid the basic pattern and main content of the thought of religious integration with Taoism in Song and Yuan. In a word, the spirt of inheritance and innovation, equal communication etc. also provides reference for today of Chinese and Western culture exchange and dialogue in assimilation of Confucianism, Buddhism, and Taoism's theory.