Abstract: The agreement that clarifies the marital property to one party should be defined as the marital property system contract recognized in Article 1065 of China's Civil Code. Its essence is an arrangement of marital property based on identity relationship and ethical relationship, which is attached to the marriage relationship and exists, which is the basis for its legal effect analysis. When defining the legal effect of the agreement clarifying marital property to one party, the value significance of factors such as marital ethics and marital function should be taken into full account with the recognition that the path and result of the arrangement of matrimonial property is affected by the appearance of common life and the moral restriction of marital relationship due to the complex social attributes of the agreement. The legal effect of the agreement shall be analyzed in the light of the differences in the internal and external effects of the agreement on clarification of marital property to one party. Within the martial relationship it should be recognized that the agreement has the effect of property right change between husband and wife, and there is no need to perform the publicity procedures such as registration and delivery stipulated by law. As for the relationship with the third party, we should differentiate between the creditor's right acquirer and the real right successor, etc. On the premise that the agreement fails to perform the publicity procedure, we should comprehensively consider and judge the effectiveness by combining the factors such as the sequential relationship and whether the third party is aware of the agreement.

Key words: marital property, agreement clarifying marital property to one party, the Civil Code, marital ethics, legal effect