Medical ethic is closely related to doctors' practicing positions.Doctors' positions on medical ethic vary a lot in the reform of medical care system: some still retain the dominant or subsidiary positions while others turn to negative positions.In profound terms,the reason why the present medical ethic and ethos deteriorate is that the demand of subsidiary positions slips into the pleonexia of negative positions.The article suggests that deterioration of medical ethic and ethos should be rectified through new theory of restraint so that humanitarian positions on medical ethic can be highly praised,demands respected and pleonexia restraint.