Abstract: This paper proposes a method for the dynamic adjustment of preventive maintenance strategies for equipments affected by unit temporary outage in view of the current situation of domestic nuclear power plants and the degradation of equipment reliability caused by temporary outage. This paper studies the identification method of equipment list affected by temporary shutdown, classifies the affected equipment and formulates the equipment maintenance strategy template. Finally, it optimizes and adjusts the maintenance strategy template to implement the application, and analyzes and explains the specific case. The results show that the adjustment of maintenance strategies for equipments affected by unit temporary outage can increase the operating reliability and maintenance effectiveness, which lays the foundation for the equipment reliability analysis during the long-term downtime of nuclear power plant units.