The human error caused by ship's navigator can be estimated as a wide ranged subject, because there should be various internal factors and environmental factors that affect a navigator's information processing system. For the purpose of preventing from accidents, it is needed to investigate not only when and how a navigator makes error and also how the error is related to the accident. The authors have constructed and also proposed the classification model of human error on marine collision accidents, in order to analyze the causes of the accident triggered by navigator's human error and to find some hazardous factors behind the error background. Finally the authors tried to verify the availability of this classification model. In this study the authors investigated 190 marine collision accidents by applying this classification model of human error and analyzed the incidental situation of the navigators' human error.