Zhouyi Cantong Qi (The Three Ways Unified and Normalized of the Book of Changes), written by Wei Boyang of the Eastern Han Dynasty (25-220), is an important canon of the Taoism and also called as Cantong Qi (Three Ways Unified and Normalized).

The principal part of Zhouyi Cantong Qi includes three sections and two attached articles (Wuxianglei and Dingqige). Zhouyi Cantong Qi mainly explains the Taoist's method to make pills of immortality and cultivate vital energy (i.e. the Dan method, including the active substances out and in the body).

Cantong Qi uses the theory of Yellow Emperor and Laozi as its theoretical basis, therefore it employs many terminologies used in the theory of Yellow Emperor and Laozi. Cantong Qi also describe the results of cultivation.