ECDIS, whose functions are to display ship's correct positions by GPS, course lines, their records, information from LADAR, ARPA, AIS, on electric charts and others, shall be said as the epoch-making navigational equipment with highly reliable and easy-to-operation, recognized by navigators. However it should be apprehensive that the characteristic of ECDIS may loss navigators' important duty of cares or norm consciousness to keep safe voyages due to it's reliable and handiness.<br>Recently, it could be said to show a marked tendency that victims and their parties committed by illegal acts strongly demand sincere apologies over legal reparation to offenders at several law cases. Victims' demands must be not only apologies but also explanations for understanding of causes or reasons in accidents. Navigators could confront to the above demands as a litigant at maritime accidents, so that they must do sincere actions which shall be established by navigators' autonomy to realize and behave duty of cares or norm consciousness.<br>The objective of these papers is to examine how to cultivate navigators' autonomy against the above problems due to navigational equipment developed. At first, it is explained that functions of ECDIS may make navigator's excessive trust in the equipment and make the said duties lost from navigators. Next, author should say the navigators' important accountability against legal and moral liabilities, and try to present ideas, applied ethics and law education for instance, to cultivate their autonomy finally.