The invention belongs to the computer graph technology field and aims to improve a scene model triangularization operation speed and reduce the triangle quantity to improve integral efficiency of a ray tracking program on the condition that ray tracking program precision is not influenced. The rapid scene model triangularization method for three-dimensional ray tracking comprises steps that (1), strings covering all the graph information are acquired; (2), bottom surface polygons, height and the vertex coordinate information are extracted from the strings; (3), each object is defined to be a DXF_Face class; (4), a polygon triangularization algorithm is utilized to realize triangularization of each surface; and (5), an opengl drawing function is utilized to display the triangularization display effect in a window. The method is mainly applicable to computer graph processing.