In the process of predicting radio wave propagation characteristics in mountain scenes by ray tracing technology, in order to improve the computational efficiency of ray tracing algorithm, an improved acceleration method based on region division and considering ray directivity is proposed. This method connects the emission point with the four vertices of the terrain triangulation model, divides the terrain surface into four regions, then calculates the intersection of each group of rays emitted by the emission point and the four edges of the terrain surface, and calculates the mesh passing through the connecting line between the starting point and each intersection according to the triangle index in the terrain model. Finally, according to the ray directivity in the vertical direction, the triangular meshes where the rays cannot intersect are further screened out to reduce the number of intersection. In this paper, the same mountain terrain is selected, and the acceleration method proposed in this paper and the traditional octree acceleration technology are used to simulate and compare the simulation results. The numerical results show that when the number of emitted rays is set to 120 × 181, compared with the traditional octree algorithm, the calculation speed of this acceleration method is improved by 50.302%, and the error is 9.547%. Therefore, compared with the octree algorithm, the algorithm implementation of the proposed method is simpler. It can improve the simulation speed and maintain small error, which has a certain reference value.