The estimation of triangular mesh curvature is implemented by establishing local quadric surface at vertexes of mesh. Deduction course of quadric surface curvature calculation is presented. Errors and complexity of two curvature estimation methods, which are the ecumenical quadric surface fitting method and the quadric paraboloid surface fitting method respectively, are compared. Technique for curvature group display is put forward. This technique can display features of mesh distinctly, even though the curvature values of mesh distribute non-uniformly in their variety range.