The relationship between labor law and civil law, specifically that of the labor contract law and civil law, has been a topic frequently discussed in the legal field for the past two decades. Domestic studies on social law focus more on the level of substantive law, more specifically around the social law of legal departments. It is difficult to draw a clear line between social law and modern civil law that emphasizes its own socialization. The study of social law demands more reflective thinking on jurisprudence and legal philosophy, through the three issues of what is the "society" of "social law", what is the "law" of "social law", and what is the relationship of the "law" of "social law" and social law, we can reveal the features of the social law. Moreover, we can also expound that, as a typical example of social law, why the labor law is hard to achieve its logical self-consistency in the civil law system. In addition, though the core of social law is the internal ethical rules of its social organism, it does not completely exclude the contract. The "trigger effect" of agreement, thus, is still indispensable, and the rules of civil law can be applied to labor disputes within certain ranges.