Abstract: In the safety architecture of pressurized water reactor (PWR), the containment structure serves as the ultimate physical barrier, designed to prevent the release of radioactive materials to the environment following an accident. The closed-type passive containment residual heat removal system (CPCCS) features long-distance efficient heat transfer, simple structure, and flexible arrangement, making it an important technical approach for PWRs to cope with various accident scenarios and ensure containment integrity. To investigate the heat transfer and operational characteristics of the CPCCS, a dedicated test facility was designed and constructed, and experimental studies were carried out. This apparatus enabled the acquisition of comprehensive experimental data on the performance of CPCCS across a wide range of simulated accident scenarios. Numerical analyses of the experimental conditions were performed using a best-estimate code. The calculated heat transfer characteristics of the CPCCS are generally consistent with the experimental results, with relative deviations between the calculated and measured heat transfer power ranging from −8.8% to −0.3%. This slight underestimation by the code provides a known and conservative margin for safety analyses. The experimental data also served as a benchmark for validating the system analysis code. Furthermore, sensitivity analysis of the CPCCS heat transfer characteristics indicates that containment pressure, partial pressure of air in the containment, and water temperature in the CPCCS tank are the most significant factors affecting the CPCCS heat transfer power and flow rate, with an optimal initial liquid filling ratio of 60%. Comparison between experimental and calculated results of the CPCCS transient operational characteristics shows that the CPCCS initiates rapidly as the containment pressure increases. The combined effect of the initially low CPCCS pressure and rapid steam generation within the evaporator leads to variations and alternations of the flow regimes at the evaporator outlet, which in turn causes certain fluctuations in the CPCCS flow rate during the startup phase. When the containment pressure finally stabilizes, both the experimental and calculated values reach steady states, with good agreement among relevant parameters. Based on the analyses, recommendations are further provided for equipment design, system layout, operation, and maintenance of the CPCCS. This comprehensive validation and analysis process is fundamental to confirming the performance and robustness of the CPCCS.