An easy adjustability of outside mirrors is important not only for the convenience but also for the crash avoidance. This paper describes the experimental study on the calculation of the driver's eye position frorn the insidc mirror's angles adiusted by himself. The accuracies of the calculation of the driver's eye position were found to tall within ±20 mm in the vertical direction and 140 mm in the longitudinal direction of the actual eye position. In addition, the accuracies were influenced by the sideways supporting of a seat. The visibility of the outside mirrors with those angles determined by the calculated eye position for the inside mirror angles was satisfactory when the outside mirrors with the convex of radius around 1000 mm were used. Results of the study indicated the feasibility of a mirror control device that would give a driver the proper rearward visibility through outside mirrors automatically.