The quantitative evaluation of fault sealing is conducted based on comprehensive analysis of mechanism and type analysis of fault seal, fault seal evaluation, and case study analysis. The results indicate that the properties of fault sealing are the interaction of fault order, net‐to‐gross ratio, fault activity, mud distribution on fault walls, fault dip, and buried depth. In addition, there are three types of fault sealing, including juxtaposition seal, fault rock seal, and cementation seal. Furthermore, the opening and closing of faults play an essential role in controlling hydrocarbon migration and accumulation. Finally, the fault sealing plays a controlling role in reservoir preservation.