本文以「歷史制度主義」為途徑，去分析毛澤東時期「二線分工」的運作與變遷。並就「歷史制度主義」的三個主要觀點，包括「路徑依賴」、「關鍵點」以及「漸續平衡」為架構，去鋪陳本文的論證。 首先，在「路徑依賴」上，本文認為因「民主集中制」的矛盾，使得中共政治在運作上，衍生出另一套非正式制度以修補之。而「二線分工」就是這套非正式制度，其目的是為了防制「民主集中制」的三項缺失，包括權力集中、非正式政治的影響以及政治繼承的危機。是故，只要中共堅持「民主集中制」，則「二線分工」就會成為一項路徑依賴，以修補「民主集中制」的缺失。毛時期「二線分工」的起點是在一九五六年九月的八大，該會決議重組中央書記處，以作為和中央政治局分工的機構。因此，開啟了毛時期「二線分工」的運作。 其次，在「關鍵點」的改變上，以一九五九年四月，毛辭去國家主席，退居政務二線為重要的關鍵。促成該關鍵點的成因上，可以「內因」和「外因」分別說明之。「內因」是起於反右運動、大躍進運動以來，逐步繁瑣的內政事務，使得毛決心辭去國家主席，以減輕工作負擔。「外因」則起於中蘇關係的惡化，使得毛有意識的了解培養革命繼承人的重要性，遂將劉少奇扶植至政務一線，以培養其接班能力。 最後，在「漸續平衡」上，在歷經一九五九年四月的「關鍵點」後，中共的「二線分工」運作由原來的「優勢政治」型演變為「權力平衡」型。在「關鍵點」之前，毛集黨務、政務一線於一身，可以直接參與黨務與政務決策的制定，因此呈現出以毛為主的「優勢政治」運作。但在「關鍵點」之後，毛雖仍居黨務一線，但因退居政務二線，所以大幅減少對於重要會議的直接參與，部分決策權轉移至劉少奇、鄧小平手中，故乃呈現出一、二線互為抗衡的「權力平衡」型。 本文在最後的結論，將討論毛時期立下的「二線分工」運作，對於後毛時期的延續性。此外，將提出中共政治的「二線分工」模式，以做為本論文的研究發現與研究成果。 / In the political regime of CCP, democratic centralism is the formal system of an organized form. “Two-front arrangement” is informal system, which is used to renovate three defects of democratic centralism, including the effects of informal system, power centralization, and the crisis of political successor. This article is used three concepts of ”historical institutionalism”, which are path dependence, critical juncture, and punctured equilibrium, to explain the transition of “two-front arrangement” in CCP. First, in the path dependence, “two-front arrangement” is a method used by CCP to repair the deficiency of democratic centralism. Second, the path of “two-front arrangement” was gone through two critical junctures of transition, one is the CCP twelve party congress in 1982, and two is the CCP sixteenth party congress in 2002. At last, the results of these critical junctures produced new punctured equilibrium . The work of “two-front arrangement” changed to patron-client type after the CCP twelve party congress and evolved to functional type after the CCP sixteenth party congress. The change of “two-front arrangement” is gradually evolving to some kinds of institutionalization. From the random type in Mao’s era, the patron-client type in Deng’s era, to the functional type in Jiang’s era, we can find that the “two-front arrangement” has remarkable function to repair three defects of democratic centralism as time went by. So we can take it as the formation of institutionalization. We analyze the “two-front arrangement” during Mao Zedong’s era. “First-front” leaders are those who participated in the policy-making process directly while leaders on the “second-front” are referred to those who only indirectly involved in the process. The article argues that the best way to identify leaders in their affiliation in the “two-fronts” division of work is to have a detailed breakdown on personnel in the highest decision-making bodies, the Politburo and the Central Secretariat. We divide Chinese leadership during Mao’s era into four categories according to official document and reputation and status of the leaders. The article further delineates the operation of the “two-front arrangement” according to the division of work between the party and the state, charisma of the leaders and formal institutions. At the end, we try to assess the impact of the “two-fronts” model on Chinese politics.