In order for the navigator to handle the ship for safe navigation, he/she judges the navigational information through the five senses. Here, we think that visual information is the most important because it is said to occupy eighty percent of the whole information. We research on the relationship between the visual environment and its influence on the ship's bridge simulator. It is used to train and educate the handling of ships as well as the handling of some navigational instruments. The purpose of this paper is to find characteristics of the body sway of the navigators and inexperienced persons for rolling created through the picture of ship's bridge simulator not physically or mechanically. The four kinds of visual field (210/spl deg/, 150/spl deg/, 90/spl deg/, and 30/spl deg/) are also carried out. The results show that the characteristic of body sway is different among navigators, inexperienced persons and seasick subjects, and the body sway tunes with the period of rolling while subjects feel the true rolling.