This paper aims at examining whether the current Korean customs punishment system is appropriate and reasonable for eliminating customs offenses, such as smuggling, and explores ways to improve the penal provisions of customs law. The current multiple fine system, governed by the penalty for evasion of customs duty, penalty for abatement and exemption by fraud or unfair practices and penalty for drawback by fraud or unfair practices, clearly violates a sense of responsibility and the constitutional principle of no excess punishment. Therefore it should be changed to a fixed fine system and confiscate and collect in addition the items with customs evasion and exemption by fraud or unfair practices.