This article introduces the economic analysis of the criminalization of the adultery from the views of parents, children, the associate and the society. The adultery in the practices is out of date, so the judges require the higher conviction than the normal criminal in order not to found the guilty. The defendant is always sentenced to a fine, even when the adultery is established. It results in the situation that only the ignorant and the poor are accused by the law. Therefore, the benefit to the injured through the criminalization of the adultery will be discussed in this article.