A method that uses 2D sectional outline curve to drive 3D mesh model deformation is presented. (Triangular mesh model denoted by) STL data format is taken as research object. Based on topological reconstruction and using the topological information of the model, the sectional outline curve that intersects by plane and triangular meshes is efficiently constructed and is presented by cubic NURBS curve. Resample the curve based on curvature distribution and make the new points as data points for curve edit, edit the curve by using mouse to interactively drag the data points on the curve. When curve shape revision is satisfied, position of data points that before and after revision are taken as constrained conditions, use constrained direct manipulation of free form deformation to make triangular mesh model deformed. This method has advantages such as it's convenient for manipulate, real-time and intuitionistic, and not necessary to build mapping relation between outline curve and vertex of mesh model.