Article 45 of the Korean Constitutional Court Act stipulates "The Constitutional Court shall decide only whether or not the requested statute or any provision of the statute is unconstitutional". Therefore, it is interpreted that only two forms of decisions, constitutional or unconstitutional, are the means of norms control. But the only two forms of decision might be insufficient to deal with all the various problems because the social problems tend to be more and more complicated. So from the early time on, the Korean Constitution Court has adopted "modified forms of decisions" such as those of "the limited constitutionality", "the limited unconstitutionality", and "the nonconformity to the constitution". The theme of this article is the problems that decision of the nonconformity to the Constitution has, because it is similar to the Japanese decision form such as "decision of appeal". It is a decision form that the Korean Constitutional Court takes account of legal stability and defers to the legislator. It has been used frequently since 1989 when it was introduced, but some problems have been appeared in operation. It must be beneficial to study the reason why these problems appear, because this kind of study may provide a useful reference for constitutional litigations in Japan.