This paper suggests a bill to amend and reform the criminal responsibility provisions of the Criminal Act of Korea, and explains the purpose of the reform. This reform bill is a part of a one-year project conducted by a group of law professors. The current criminal act was enacted in 1953 and its general part remained intact ever since. So it is thought that amendments are inevitable to introduce new theories and court decisions in the field of criminal law. On the question of the criminal immaturity excluding the criminal responsibility, the authors accepted the current provision which excludes the criminal punishments of a person, where he is less then 14 years of age at the time of an offence(Article 9). A recent amendment to the Juvenile Act authorised protective measures to a person between 10 and 19 years of age. About a mental disorder the authors considered recent developments in the psychiatrics. The effect of diminished capacity or partial capacity is needed to be changed. The current regulation provides that "for the conduct of a person who, because of mental disorder, is deficient in the abilities mentioned in the preceding paragraph, the punishment shall be mitigated." The principle of responsibility requires that the punishment shall be proportionate to the responsibility of a person. Under the current article 10 paragraph 2 a punishment shall be mitigated, where a perpetrator was however diminished in the capacity provided for in Article 10. This kind of lenient punishments do not seem to comport with the justice principle. So this bill gives a discretionary effect of the partial capacity. The self-induced intoxication has been in the middle of dabate in last 10 years. The new provision gives a clear ground for the negligent self-induced intoxication and knowingly induced intoxication(so called actio libera in causa, Article 10 para. 3). On the mistake of law(art. 16), the courts have been of the opinion that the art. 16 does not apply to the case of ignorance of law, while the academics interpret the provision to the contrary. The new bill places explicitly the ignorance of law under the same theory of the mistake of law, by which a person shall not be punishable if the mistake is based on justifiable grounds.