This paper describes a basic research results on the engineering visibility evaluation of the horizontal scroll display character in the LCD screen．It is studied subjective visibility of Japanese text that flows through the LCD screen in a single line from the right to the left. Text information of the random arrangement “katakana” is used. The scroll speed, number of characters and the character size are investigated the effect on visibility. Certain of the character size and the number of characters that visibility is improved exist for the LCD screen size. To obtain a scroll speed suitable for the number of characters and character size, it is possible to improve the visibility. This study is considered to lead to obtain the guidelines for the future, improve the visibility of the dynamic character information.