To put the binocular 3-D images system into practical use, it is required to investigate the relationship between the system and men and to make ergonomic evaluation of the system. In this study, we perform a comparative analysis of the changes in the accommodation and pupil functions before and afer observing binocular 3-D images a sthe visual distance varies. From the experiment, we obtained the following results: (1) The discordance in the distance informatioons on the accommodation and pupil functions when obwerving 3-D images is compensated by the miosis and altering the focal depth. (2) From the consideration of the effect of the visual distance condition on the visual functions, it is thoughth that the visual functions are stabilized at the dark focus in the sense that the changes in the tension and relazation afer observing the 3-D images are minimized.