Abstract: Using triangular Bézier patches to reconstruct surface from scattered points possesses many advantages in reverse engineering．NC programming techniques based on triangular Bézier patches for surface machining and pocket cutting are studied．Several forms of workblank definition are presented．Rough cutting schemes such as layered-cutting with variable-cuttingdepth and layered-cutting with constant-cutting-depth are proposed for different workblank forms．Moreover the tool path planning and cutter location calculation is also discussed．