Abstract: Passive containment heat removal system (PCS) is used to deal with the beyond design basic accidents of HPR1000. The general configuration of the system was described, and then the effectiveness of this system to deal with beyond design basic accident and severe accident was analyzed. Based on probabilistic safety analysis, the impact of PCS on core damage frequency and large radioactive release frequency was analyzed. The results show that PCS has a significant effect on enhancing the prevention and mitigation of severe accidents of HPR1000 and can effectively enhance the safety of HPR1000.