Abstract: The computation of radiation indirect drive from hohlraum to the capsule in the symmetry analysis of inertial confinement fusion(ICF) is difficult to deal with occlusion culling and low efficiency.With respect to these defects,a parallel algorithm based on computing unified device architecture(CUDA) is proposed for the computation in thermal radiation on implosion pellet.Firstly,based on the equivalent model of two-region uniformly,the interior wall of hohlraum and the surface of target are divided into grid cells.Then those cells are organized by a quad-tree structure to construct hierarchical bounding box.The obstructed cells can be excluded quickly by the intersection judgment among these boxes.Finally,to realize the parallel computation of energy flow distribution,the calculation processes of view factor are mapped to GPU threads.The experimental results show that the presented algorithm can achieve a speed-up ratio about 15 with considering occlusion,and 400 without considering occlusion.