Chanmen Guishi written by the Zen-master Baizhang-huaihai is the Pioneering Work of Chinese Buddhist Monastic Code (Qinggui), and Chanyuan Qinggui compiled by the Zen-master Cijue-zongze is the earliest extant one. Through the comparative study of the Chanmen guishi's remnant and the Chanyuan Qinggui, this paper attempts to clarify the true inheritance relationship between Chanmen Guishi and Chanyuan Qinggui. Based on that, this paper further analyzes the succession and abandonment of the Pioneering Work in the following Buddhist Monastic Code (Qinggui).