Current methods of computing height of antiglare facilities at median strips of highways are relatively approximate and inaccurate,because the 3D features of highways are not taken into consideration.In order to obtain rational and effective height of antiglare,an innovative three-dimensional computing method is proposed in this study.Based on the hypothesis that illumination range of vehicle light is of a pyramid shape,an algorithm is established with Matlab to simulate the space illuminated by headlamp during driving.A method is proposed to obtain viewpoint coordinate sets affected by glare when a vehicle is in any position.With the principle that the highest point of one antiglare facility is just on the line which connects viewpoint and light source,anti-dazzling heights of antiglare facilities at all positions can be successively computed by Matlab.A case study shows that the heights of antiglare facilities can be directly obtained using this method with necessary input data.