Ship is divided into four stages depending on whether the crew is on board and whether remote controllers are controlled, and fully Autonomous Ships will make optimal decisions based on algorithms designed by designers without human intervention. However, due to the characteristics of Artificial Intelligence such as autonomy and unforeseeability, the decision of a fully autonomous ship cannot always be expected to be ethical. However, Artificial Intelligence should make decisions that reflect human values. Especially in situations where the risk of conflict is unavoidable so called accidental algorithm, it should be able to explain what principles and criteria Artificial Intelligence makes decisions and these decisions should be reasonably accepted by society. This discussion of the ethical issues of Artificial Intelligence is the most active in the field of self-driving cars. However, there is a limitation that human values are difficult to have consistency and universality. In particular, in ethical dilemma situations, "Dualism of Practical Reason" makes decisions different from rational and ethical judgments, and standards for ethical behavior are also recognized differently depending on regional, cultural, and economic situations. As a result, while recognizing the need for ethical guidelines for Artificial Intelligence, it is skeptical about establishing specific standards. Because the ethical dilemma situation of self-driving cars cannot be predicted and fully responded to the real problems that will arise in the process of use. However, coming up with countermeasures after the problem occurs is only a measure to remedy the damage that has occurred in reality and is not a way to solve the fundamental problem. In particular, Maritime Autonomous ships operating in waters all around the world must make decisions that are reasonably accepted by world society. Therefore, Ethical guidelines, including accidental algorithms, should be prepared by the International Maritime Organization and reflected their legal system in individual countries. In the entire process from the development stage to the use stage, program developers and stake-holders will have to comply with Ethical standards and respond to Maritime Autonomous Surface Ships’s ethical issue through complementary work based on accumulated information.