This research investigated the objective indexes of better design for computer screen by using the eye movements of operators. Conventional computer techniques are based on a multi-windows concept in a single screen. Although this can be a beautiful and intelligible screen, characters and windows may lay one upon another, and it takes much time to access the desired information. In this paper, the gazing points were measured for these screens : Microsoft Windows, Macintosh OS (9, X), and X window system, and the following tasks for each OS : documents production and editing, file operations, OS operations and execution of programs. The distance of each gazing point, speed of movement, the fixed duration time and fixed positions were quantitatively evaluated from these data. From the results, the design indexes relating to cursor movement, the position and design of icons, menu display position and window size and position were investigated.