宋明理學時期的思想是中國哲學思想中非常重要的一環，其中，對於宋明理學的分系問題，一直是當今學界討論的焦點，其中又有二系說、三系說、一系說（一系三型說）的爭論，本文即以此問題為核心，重新思考宋明理學分系的問題。首先提出學界一般以程朱與陸王分為二系的說法無法盡學術之實與義理之全；進而提出對於牟宗三先生三系說的重新思考，認為三系的分判最可以將宋明理學的義理真相分清楚。最後分析勞思光先生所提出的一系三型說以及大陸學者慣於使用的三本論（性本、心本、氣本）之問題所在，並指出牟宗三先生的三系說統括了「縱貫系統」與「橫攝系統」，兼顧自律與他律，因此為我們對於宋明理學分系的最適合的理論。因此本論從以下五個面向加以深究：一、濂洛關閩之說無關義理系統；二、程朱陸王二系說之分判有不盡；三、宋明理學三系說的省察；四、一系三型說（天道觀、本性觀、心性論）的問題；五、三本論（性本、心本、氣本）立名之檢視。

　　　　　Neo-Confucianism in the Song and Ming Dynasties was an integral part of Chinese philosophy, whose different schools are the focus of the academia nowadays while it is still being argued whether there are two schools, three schools, or just one school that consists of three styles. All the above is the center of this paper from which to re-consider the schools of Neo-Confucianism. First, we point out that the two-school doctrine (one of the Chengs and Zhu Xi, the other of and Lu Jiu-yuan and Wang Shou-ren) is neither academically truthful nor theoretically complete. And we further re-consider Mo Zong-san's three-school doctrine, which we assume can clarify the theoretical truth about Neo-Confucianism. Finally, we analyze the problems with Lao Sze-kwang's doctrine about one school of three styles as well as point out how Mo Zong-san's three-school doctrine integrates “longitudinal studies” and “transversal studies”——including both self-discipline and external supervision——and therefore is our most appropriate theory about the schools of Neo-Confucianism. Therefore this paper is to explore the topic through five aspects: first, the Lianluo Guanmin’s doctrine is not concerned with theoretical systems; second, the two-school doctrine is incomplete; third, a reflection on the three schools of Neo-Confucianism; fourth, the doctrine about one school consisting of three styles; and fifth, the three-school doctrine held by scholars in mainland China.