Since the 18th National Congress of the Communist Party of China,in the great practice of advancing the Party's self-revolution in the new era,Xi Jinping,with his consistent sense of unexpected development and firm perseverance in facing up to difficult problems,put forward a series of new thoughts,viewpoints on the causes,core contents and solutions of the unique problems of the major party,which effectively promoted the theoretical exploration and practical response to the unique problems of the major party and made historic a-chievements that have attracted worldwide attention.It deeply demonstrated the political,strategic and his-torical initiative of our Party in party governance,which is of great significance in theoretical innovation and of leading contribution to the world.As an integral part of Xi's important thoughts on party building,his impor-tant expositions on the unique problems of the major party is not only a solution to the new problems and challenges that arise in party building in the new era,but also contains distinct methodological implications and theoretical value,making significant original contributions to enriching and developing the Marxist theory of party building.It is highlighted in the following dimensions:in terms of academic original contribution,Xi systematically constructed a logical system and analytical framework for the unique problems of the major party,proposed the original concept of"the unique problems of the major party",the brand new proposition of"we must always stay alert and determined to tackle the unique problems of the major party",and the stra-tegic consideration of"the six strategic tasks",achieved the theoretical sublimation and leap of the Marxist theory of party building.In terms of innovative expansion contribution,Xi examined,analyzed,and solved the unique problems of the major party by combining prominent issues of the times,Chinese historical wis-dom and human political civilization.He broadened and deepened the content,category,perspective and vision of the Marxist theory of party building both diachronically and synchronically,and thus formed a scientific theoretical system that met the general requirements of party building in the new era.In terms of creative ap-plication and contribution,Xi flexibly applied the value stance,core viewpoints,and ideological methods of the Marxist theory of party building to analyze and solve the unique problems of the major party,and promo-ted this theory to release strong theoretical charm and practical effectiveness with the change of the times.In summary,Xi's important expositions on the unique problems of the major party contains distinct theoretical characteristics,including unwaveringly adhering to the basic principles of the Marxist theory of party build-ing,as well as persevering in responding to a series of new major issues facing the Party's long-term govern-ance.At the same time,it is rooted in the fertile soil of the Chinese history and culture and world civilization to enrich the Marxist theory of party building,enhancing the systematization and theorization of the Marxist theory of party building with Chinese characteristics.Consequently,they offer important methodological en-lightenment and ideological reference value.