As a scholar of Zhu Xi's doctrine, Zhen Dexiu's theories about "mind" is similar to school of heart/mind. The topic will compare Zhen Dexiu's Xinjing with shishandu shuji to present features of the content, structure and thought. Extending from Xinjing, we also can find the similarities and differences of "Mind Theories" between Zheng Dexiu and Zhu Xi. Zhen Dexiu is certain of mind's original state, attaching importance to the place of "Weifa" and the self cultivation of "Stillness". He also emphasized the feeling of "Jieju" which "seems to face god". All of these are the development of Zhu Xi's theory.