This study critically examines Korea’s ship defect reporting system under the Ship Safety Act, focusing on legal clarity, proportionality of punishment, and alignment with the Aviation Safety Act and Railway Safety Act. In response to major maritime disasters like the Sewol Ferry and Stellar Daisy, the law has imposed stricter reporting obligations and harsher criminal penalties. However, unclear definitions of reporting entities, vague defect criteria, and criminal punishment for minor violations raise constitutional concerns. Through doctrinal legal analysis and comparative study of the Aviation Safety Act and Railway Safety Act, this paper highlights inconsistencies and legal ambiguities. It proposes a long-term shift toward a voluntary reporting model and recommends short-term legislative reforms, including clearer definitions of obligated parties and defects, specific reporting deadlines, and replacing criminal sanctions with administrative fines for minor breaches. These measures aim to enhance the effectiveness, fairness, and constitutional validity of maritime safety regulations in Korea.