Based on an integrated severe accident analysis code, a severe accident analysis model is established to include the Reactor Coolant System (RCS), the Engineered Safeguard Facility (ESF) and the containment system, coupled with a thermo-hydraulic analysis, the containment response and the fission products behavior. A passive containment cooling system model is also built with consideration of the air convection cooling and the liquid film heat transfer. Three typical severe accidents induced by small break loss of the coolant accident (SB-LOCA), large break loss of the coolant accident (LB-LOCA) and loss of the feed water accident (LOFW) are considered with the containment atmosphere decontamination as a result of the passive containment cooling mechanism. For every sequence, three different cases are considered, which are the case without cooling, the case with air convection, and the case with air convection and liquid film. The aerosol behaviors for different cases are studied focusing on the volatile fission products and non-volatile fission products. The results show that the passive containment cooling mechanism can enhance the removal effect of diffusion phoresis and thermo-phoresis.