庚信身處動盪不安的南北朝時代，在南梁尚未覆滅之際，他出使北國，羈留北朝任官，至南朝由陳代梁之際，庾信淪為新、舊認同之的異鄉客，在時空巨大變遷的歷史中，其人生境遇與生活環境的轉變，迫使他找尋人生的定位所在。由於庾信受士族門閥制度的影響，在家世道德、家族認同的統觀念下，是不應仕北的，然則在歸隱不得的情形下，在沮喪失望之餘，他也理所當然順應時代的趨勢而出仕北朝，此時，庾信本來認為不應仕北的「我」與特重忠君的「我」，因為改朝換代，全都變了樣，此其一也。然則南士族在朝廷更迭的治認同模式皆以士族利益為牨次序，若對其家族有利，儘可能幫助君王篡位，始終是先孝後思，先父後君的觀念，沒有必要忠族一君，庾信在現實的作為上，同南朝士族一樣，歷仕朝朝，重視家族利益，此其二也。在庾信的內心深處因家世道德、家族認同，塑造出一個不應仕北的「我」；在現實的作為上，庾信卻歷仕諸朝。當同一時代的南朝士族對庾信的看法與庾信自身對自己的看法不同時，於是迫使庾信產生了「我到底是誰？」的認同危機。本文即思以前人之說為基礎，在既有的研究成果上，從另一角度對於庾信的政治認同作闡釋。庾信為滿足心王深層的廉屬建構，而創作出感人肺腑的作品，然則他始終無法國到他所認同梁朝的政治身分，唯有透過想像而解決當下的困境，在求認同的過程中，庾信始終是一個沒有家的人，他是一個飄泊的人。

Yu Xin was born during southern and Northern Dynasties, which was period of chaos. Before Liang in Southern Dynasties was extinct, he was sent to Northern country in Northern Dynasties on a diplomatic mission and was detained to be a Northern official. At the moment of dynastic changes from Liang to Chen in southern Dynasties, Yu Xin was forced to orientate his life during this transition. There was a contradiction between Yu Xin’s traditional thought and action. With the influence of the traditional Chinese family, Yu Xin was not supposed to serve Northern Dynasties. On the other hand, the profit of family was thought to have higher priority than the profit of country during that period. According to the profit of family and the reality that his apply of retirement was not permitted, Yu Xin served in the second country. With this contradiction, the crisis of political identity occurred in Yu Xin’s mind. The crisis of political identity not only responded Yu Xin’s wandering between Southern and Northern Dynasties, but also enabled Yu Xin to produce a lot of touching literatures.