Aiming at the problem of contact region defects,broken in outer of passive gear and input bevel gear shaft,poor interchange ability and so on caused by cutting interference in the Klingelnberg spiral bevel gear pair,and the cause is analyzed.Some improvement methods are put forward from contact trail readjusting,reducing meshing impact,material,process controlling etc.Through the proper process adjustment,the quality of the contact region can be improved,the interference can be eliminated and the life of gear and interchangeability are improved.