For the design guide of a vessel operating in cold region, numerical analysis was carried out to evaluation weather-tight door and ice class louver which installed the heating cables by using ANSYS 13.0. This study based on the experimental results of ‘A Study on Anti-Icing Technique for Weather-Tight Door of Ice-Strengthened Vessels’ and ‘The Cryogenic Performance Evaluation for the Excellent De-icing Ice Class Louver’ in KRISO. The numerical analysis of weather-tight door was performed by considering Advection-Diffusion equation. In case of ice class louver`s numerical analysis was performed by considering RANS(Unsteady Reynolds Averaged Navier Stokes) equation. The numerical analysis results applying the same specifications and the position of the temperature sensor compare with the cold-chamber experimental data for validation of numerical analysis. The design variable factors of weather-tight door external environmental temperature(0, -10, -20, -30, -40℃, -55℃), power output of heating cable(33, 45, 66), the thickness of pipe(0.5, 1.0, 1.5) were performed total 48 cases numerical analysis. And then, the design variable factors of ice class louver external environmental temperature(0, -15, -30℃), relative velocity(1, 4, 7), power output of heating cable(33, 45, 66), location of heating cable on blade(top, center, behind) were performed total 81 cases numerical analysis for most efficient and anti-icing & de-icing design guide of weather-tight door and ice class louver.