A design algorithm of a triangular mesh model was proposed, that included four steps: first, the reference surface of the triangular mesh model was obtained with least square method; second, the projection point of vertex on mesh was calculated and the mapping relationship of mesh vertex and projection point was built; third, the coordinates of mesh vertexes were changed according to the displacement of projection points when adjusting the control points of reference surface; and fourth, the fairing of mesh model was built with triangular Bézier surface design method, which proved that the deformation region of triangular mesh model was effectively controlled. The smoothness of mesh model and the efficiency of innovative deformation designing have been improved effectively.