內藤湖南提出「唐宋時代觀」下所附帶的中國史分期論，戰後以來成為日本中國史學界的討論框架。以「貴族制」作為魏晉南北朝史(六朝史)主要命題的論點，也被戰後研究魏晉南北朝史的學者接受，並圍繞著相關主題將「六朝貴族制」的說法繼續深入討論。其中，谷川道雄尤其注意內藤湖南提出的說法，除了重視貴族的文化層面之外，更自貴族與社會層面的連結補足了內藤氏論述較不足的論點，衍生出「中世共同體」的學說，以此作為魏晉南北朝隋唐史屬於中國中世的主要註腳。唐長孺發展出唐代中後期「南朝化」理論，作為唐氏討論中國歷史發展軌跡的重要論述，同時提出了南北朝歷史路線說，闡明中國封建社會的變遷。唐氏以社會經濟的變化作為中國史分期的基準，揉合了傳統史觀與馬克思史學框架，展開對中國史長期發展趨勢的分析。本文試圖比較中日雙方的代表觀點之異同，藉此深化對魏晉南北朝史的認識。

In the beginning of the 20^(th) century, Naitō Konan (1866-1934) brought up the idea of the Tang-Sung transformation and a following periodization of Chinese history (known as the ＂Naitō Hypothesis＂). This theory became a paradigm generally accepted in the academic community of history in Japan after World War II. Following a thesis mainly concerning aristocracy, Six Dynasties scholars elaborated studies in that topic and related subjects in that period. Tanigawa Michio paid special attention to the ＂Naito Hypothesis,＂ but in addition to the cultural aspect, he also underlined the connection between the aristocratic clans and the society, to which Naito failed to give sufficient consideration. Tanigawa thus brought up the thesis of ＂the Middle-Age community＂ to support the periodization of Chinese history in which the Six Dynasties period is included in the Chinese Middle Ages. Influenced by Ch'en Yin-k'o, Tang Changru elaborated Ch'en's theory of ＂South-Dynastirization＂ and rendered it his important approach to the periodization of Chinese history. Futher, he raised a schema of two different historical paths which the North and the South Dynasties took respectively, in order to clarify the vicissitudes of the feudal society in China. Tang took socio-economic changes as the criteria when periodizing Chinese history, combining traditional and Marxist views and studies of history. The aim of this article is to draw a comparison between the representative theories and viewpoints of the history academic circles in Japan and those in Chinese studies, whereby we may reach a deeper understanding of the Six Dynasties period.