Based on the contract documents about five villages in southern Shanxi Province collected by Tsinghua University, contract inscriptions published in North China, and official and local history materials, the shuidi, shuifen, shuilu, shuidao and shuidi, which are closely related to land management and farmers' life, are brought into the research field of land and house transaction. For land transaction, whether there is a stable irrigation water source directly affects the way and price of land transaction, which has become one of the criteria for tax division. In the systematic and networked water rights management and distribution system, there is an imbalance between the acquisition of water and the actual market demand for irrigation water. Water is sold separately, and the government and non-governmental organizations prohibit it from the perspective of social stability and tax collection. The tension of the two results in the coexistence of separate water sales and land water sales. In addition, in land transaction, the right to use irrigation waterways owned by individuals is often clearly stated and stipulated. For housing transactions, the waterways directly drained by farmers' houses and yards are owned by individuals, and an explanation is added in the transaction. As two functions of drainage and boundary, shuidi often plays an important role in neighborhood disputes. It is often explained in accordance with folk customs in order to ensure the stability of rural society.