Numerical simulations of Huygens probe entry flowfield are carried out using the thermochemical nonequilibrium code loosely coupled with one-dimensional and three-dimensional radiative transfer. A modern multi-band model is used in the radiation calculation. In one-dimensional radiation calculation, the tangent-slab approximation is employed. In three-dimensional radiation calculation, on the other hand, the ray-tracing approach is employed in the direction of the Gauss quadrature point for the integration of the radiative intensity over the solid angle. In the tangent-slab approximation, the calculated radiative heat flux values agree well with those given by the previous Huygens probe entry flowfield prediction. In three-dimensional radiative transfer calculation, the radiative heat flux at the stagnation point becomes about 25% smaller than that given by the tangent-slab approximation due to the body curvature. On the other hand, the extent of reduction of the radiative heat flux values from those given by the tangent-slab approximation around the mid-cone region becomes less than that around the stagnation region.