Administrative contracts are a flexible way that administrative agencies implement to achieve administrative management goals. Compared with unilateral administrative actions, administrative agencies are more inclined to sign administrative contracts in order to achieve administrative management goals. Determining the invalidity of administrative contracts is the core content of the administrative contract system, which involves the application of law when judges try cases. It is controversial how the court applies the rules of private law, especially the mandatory validity provisions, in the trial of administrative contract invalidation cases. This article focuses on mandatory effectiveness regulations, sorting out the differences in understanding of mandatory effectiveness regulations in civil law and administrative circles, summarizing the judgment ideas of the court when trying administrative contract effectiveness cases, and pointing out the existing problems.