Abstract: Pressurizer level control system (PLCS) is one of the key subsystems of distributed control system (DCS) in nuclear power plant, which is responsible for regulating the amount of primary coolant. In this paper, a Boolean logic-driven Markov (BDMP) model was used to construct a PLCS dynamic reliability model, and a method of converting BDMP to a Markov model was proposed. The probability model checker PRISM was used to analyze the converted Markov model. After quantitative analysis, the unavailability rate of PLCS and the contribution value of different components to the unavailability rate were obtained, and then KB3 and YAMS were used for modeling and quantitative analysis. The quantitative analysis results were compared with the PRISM results and the effectiveness of the method in this paper was verified. The method in this paper provides direction and reference for the maintenance of PLCS of the nuclear power plant.