Abstract: To solve the problems of the existing triangulated irregular network（TIN） model voxelization algorithms which could not find all required voxels or had a poor time efficiency in some cases, a fast TIN model voxelization algorithm was proposed. This algorithm has 2 steps: surface voxelization and solid voxelization. In the surface voxelization step, all triangles are voxelized by using single triangle voxelization algorithm based on geometric intersection computation. The single triangle voxelization algorithm computes all vertices of the triangle-cross-voxel polygons, and corresponds the vertices to the voxels; In the solid voxelization step, the seed fill approach based on scan line and length-changeable queue structure is used to fill all voxels inside and outside the TIN model, which spends less memory. Experimental results show that this algorithm has a good time efficiency when voxelizing precise model and TIN model with more triangles.