Since the 18th National Congress of the Communist Party of China （CPC）， General Secretary Xi Jinping has， from a cutting-edge perspective， creatively put forward a series of original and landmark new concepts， ideas， and strategies， forming his important thoughts on the Party’s self-reform. This systematic theory answers fundamental questions such as why the CPC needs self-reform， how it is capable of self-reform， and how to deeply advance self-reform， which serves as a crucial theoretical guideline for the Party management and governance in the new era. General Secretary Xi Jinping’s important thought on the Party’s self-reform is an important achievement of the Communist Party of China （CPC） in advancing theoretical innovation by adhering to the “two combinations”， which embodies a scientific theoretical logic， a profound historical logic， and a distinct practical logic. This major theoretical achievement signifies that the CPC’s understanding of the law of building a Marxist ruling party has been sublimated to a new realm， and has achieved a new leap in the Sinicization and modernization of Marxist party-building theory. A thorough study and profound comprehension of the constructive logic and theoretical contributions of General Secretary Xi Jinping’s important thoughts on the Party’s self-reform will surely deepen our understanding of the Party's self-reform，and further advance the study and implementation of this important thought.