In this article the author tries to find an element in dolus eventualis case that makes it a crime with criminal intent, not of negligence. For that purpose he analyzes mens rea, the subjective element of crime, and tries to compare the theories of dolus available in korean criminal law scholarship. Korean criminal law does not have any category similar to ‘recklessness’ in anglo-american law, so the cases subsumed by that category should be classified as either crime with intent or negligence. The author insists after some theoretical investigation on the themes around the criminal intent that the essential element in the dolus eventualis cases the criminal’s attitude of taking result seriouly during committing a crime. So if a criminal took the result seriouly, which at last occurred after her performing some activity, the result can be regarded as committed with criminal intent.