This article discusses the hermeneutic model in Zhu Xi's philosophical thinking: the relationship between zhi and xing is treated in the first section, and that between jing and quan in the second. The former section explores issues relating to elements of knowing (zhi) and doing (xing), in the sense of moral philosophy; and the latter, in the light of ethics, ponders the ways of grasping the constant principles (jing), and the ways of carrying them out by expedient measures (quan). These are originally concepts of epistemology, ethics and practical philosophy, not that of hermeneutics. Nonetheless, in the interpretation of classics, a Confucian scholar has to offer advice on how to comprehend the teachings of the texts as well as on how to apply the universal principles in concrete moral situations. In this connection, such ideas as "knowing-doing" and "constancy-expediency" have strong hermeneutical significance. This article argues that in Zhu Xi's philosophy, both the epistemological-practical model of "knowing-doing" and the ethical-practical model of "constancy-expediency" have hermeneutical dimensions.