本文以元末寓居蘇州的士人陳基（1314─1370）為研究對象，考察其一生經歷，特別是寓居蘇州期間的政治、社會、文化活動。蘇州在元代是為平江路，元末動亂不安之際，不少士人遠走他鄉以避災禍，蘇州是上選之地。陳基起初並非因避難而寓居蘇州，不過卻因為寓居蘇州，使得陳基經歷蒙元、張吳、朱明三個政權的統治。透過對陳基一生經歷的考察，一方面探討一位寓居士人如何融入當地社會進而有所貢獻；另一方面闡述陳基奉元為正朔的態度，以及選擇支持張吳政權的意義。奉元為正朔與支持張吳政權，也成為陳基不明顯正面支持朱明政權的主因。陳基奉元為正朔，在於承認蒙元政權的正統性，無關異族統治；支持張吳政權，則是在奉元為正朔的前提下，加上張吳政權「保境安民」、「禮下賢士」的角色獲得士人認同。陳基的個案研究，可以提供理解元明之際江南士人對於政權選擇的另一個註解。

This article is to discuss the sojourner（流寓） Chen Ji’s（陳基） political, sociological and cultural activities during his stay in Su-zhou（蘇州）. Su-zhou, also known as Ping-jiang route（平江路）in Yuan Dynasty, was a better place for people to live before turmoil got everywhere at the end of Yuan. Taking refuge was not the prime reason for Chen Ji to stay in Su-zhou, however, his stay in Su-zhou encountered three political changes from Mongol-Yuan（蒙元）, Zhang-Wu（張吳）to Zhu-Ming（朱明）. By understanding his lifetime, this article discusses how Chen Ji joined and contributed to local society when he stayed in Su-zhou. It also explains why Chen Ji recognized Yuan as legitimacy and supported the Zhang-Wu regime that made him reject the Zhu-Ming regime. It is no concern of Mongol rule that Chen Ji recognized Yuan as legitimacy. And the reasons he supported Zhang-Wu were because the Zhang-Wu regime not only recognized Yuan as legitimacy but also kept Su-zhou safe and respected the literati. The case study of Chen Ji can provide a commentary to the literati in Jiang-nan （江南）area choosing political ruling throughout Yuan-Ming transition.