The Ji clan in Longquan county began to compile genealogies from the Jiaqing reign period, Qing Dynasty. The ''clan norms'' in the genealogies formulated the rules of li si (inheriting the identity to worship the ancestors). According to these norms, one person must get the identity of si zi first and then he had the right to inherit the clan property. By determining the identity of the heir, clan delineated the clan scope and established the clan's economy order. These clan rules were supported by the Qing law. The Succession Part of Civil Code was enacted in 1930 and the ancestral inheriting system was abandoned. This law change impacted the clan system's foundation. With the new found lawsuit archives and genealogies in Zhejiang Longquan, we explored how the local clans dealt with this challenge from the law reform in the Republic of China. The Ji clan rebuilt the genealogy and amend the clan norms between 1929 to 1932, which was a positive response to the change of the civil law. Ji clan held the clan council to discuss the controversial affairs in li si and formulate the new clan norms, including the court judgments in the previous heirs disputes. For example, in a legal dispute about li si, the court supported a child as an heir from another different surname. Regarding this dispute, the clan council had to admitted the court's decision, but only as a special case. On the contrary, the new clan norms emphasized that adopted son with different surname cannot inherit as si zi. By emphasizing the ''democratic procedures'' in clan council, the compilations of the Ji clan genealogy wished to give the new clan norms more legitimacy. Overall, the new norms had kept the ancestral inheriting system and the relationship between the li si and property inheritance. ''Clan norms'' is regarded to the supplement of the civil law. The contradiction between them was skillfully evaded in the former. Although the clan council tried to adjust the relationship between the clan norms and the new civil law, but the clan members still challenged the clan council resolutions. In 1933〖CD*2〗1934, Ji Liangwen, a clan member who was eager to inherit a distant ancestor, initiated legal proceeding against the clan leader because he had not been recognized as si zi in the new genealogy. But Ji Guanzhou, a council member and proficient lawyer, intentionally guided the proceeding to argue that the clan leader individual cannot represent the whole council and avoided discussing the descent problem itself. Since the civil law no longer had any regulations about li si, the clan council which actually advocated stricter rules of li si, or the clan member who claimed that he was qualified to inherit ethnic descent, were unable to get support from the civil law. Nevertheless, the council, based on the concept of the modern democracy, won more legitimacy for the new clan norms. The amendment of clan norms were a response to the reform of the civil law in 1930, and also an adaption to the daily disputes and proceedings among the clan members. The rules formed in disputes and court decisions affected the clan norm amendment by the clan council. In this sense, the relationship between clan norms and the civil law is not only the reflection of the relationship between the clan and the state, but also shows the relationship among the clan members. The clan transformation in modern China and the practice of the civil law were promoted in the participation and contention among clan elites and other clan members. The new rules were operated, confirmed and changed in the disputes, mediation and proceedings among clan members.