This study review Korean Supreme Court's case on police stop and questioning. Korean Supreme Court admits some forcing for police questioning under considering of Principle of Proportion. This suggestion of Court is based on try for activity of operation the police. However, there is no legal source that Court's resolution. I think Court have to decide for liberty of civil, not criminal justice system when it is vague. I think under current the Act on the Performance of Duties by Police Officer, it is impossible to exert some forcing for police questioning.