Abstract: To simulate the fluid dynamic and thermal characteristics in sodium pool accurately, newly three-dimensional hot pool analysis model with porous medium model and complex geometry was developed after incorporating the porous model of penetration components into three-dimensional model developed already for system analysis of pool-type fast reactor. Penetration components include intermediate heat exchanger, primary pump, decay heat exchanger, and radial shielding. After coupling with the system analysis code SAC-CFR, the newly coupled code was applied to analyze the flow field in hot pool-under steady-state operation condition and after scram. The agreement between the computational flow field and the geometry of hot pool shows the effectiveness of porous medium model, which makes preparations for further development of passive residual heat removal system.