Abstract: This paper argues although legal instrumentalism is rational, absolute instrumentalism is not.Similarly, criminal law instrumentalism likewise is legitimate, but over-instrumentalism of criminal law is bound to cause a cancerous growth of the penal power of the state and the severe shrink of civil right and liberty.In legislation, over-instrumentalism of Criminal Law which is represented as overcriminalization, and in criminal justice, is symbolized by judicial discretion and power of over-extensive interpretation.The basic strategy of being vigilant against it is：stand the“criminal law as last resort”ground in legislation, while criminal justice system thoroughly implements the legality principle and strict interpretation.

Key words: Legal Instrumentalism and Non-Instrumentalism, Over-Instrumentalism of Criminal Law, Overcriminalization, Criminal Judicial Discretion, Legality

摘要： 法律工具主义虽然有其合理性，但不可绝对工具主义化；同理，刑法工具主义亦具有正当性，但刑法过分工具主义化必将导致国家刑罚权的恶性膨胀和公民个人权利与自由的严重萎缩。刑法过分工具主义化在立法上表现为过度犯罪化，在刑事司法上则表现为司法裁量权与解释权的过度扩张。防止刑法过分工具主义化的基本策略是，立法上坚守刑法乃最后手段立场，司法上彻底贯彻执行罪刑法定原则以及严格限制刑法解释。

关键词: 法律工具主义与非工具主义, 刑法过分工具主义化, 过度犯罪化, 刑事司法裁量权, 罪刑法定