In recent years there are many legislations that raise the limit of punishment. For example, the maximum of the imprisonment has been increased double since 2012. And some special criminal Acts has been enacted that represent ‘tough policy’ toward crimes and criminals. Therefore there are many appeals of the unconsitutionality of these Acts. But Korean Constitutional Court has shown very passive attitude in the reviewing of the unconstitutionality of these Acts. The purpose of this paper is to critisize the attitude of Korean Constitutional Court and to suggest some desirable alternatives. The contents of this paper is as follows : I. Introduction II. The Principles of Legislating Criminal Law 1. Legislative Discretion and its` Limits 2. Subsidiarity and the Proportionality of the Punishment 3. Positive Comparison III. Kcc`s Attitude toward the Unconstitutionality of the Harsh Punishment 1. The Basic Position of the KCC 2. The Crime of Hit and Run 3. The Robbery causing Injury(KCC 1997. 8. 21. 93Hunba60) 4. The Crime of Sexual Violence(KCC 2013. 7. 25. 2012Hunba320) IV. The Desirable Attitude of the KCC in Reviewing Unconstitutionality 1. The Elements of Evauluation 2. The Character of the Crime and the Purpose of the Provisions 3. History and Culture, and the Social Situation 4. People`s Attitude toward Crimes and the Criminal Policy V. Conclusion