To reduce a visual recognition burden through the reducing of information amount in moving rather than information at the time in stopping by controlling specified information with information to be supplied to a display means and controlling display areas to be displayed on a display screen.

An electronic map information guide is prepared by inputting a destination to a CPU 1. When a preliminarily set moving speed is sensed by a speed sensor 6, an information reducing program is actuated and, then, information capable of being indicated on the display means 2 are controlled to be a proper timing, proper kinds and a proper amount by being made to correspond to the speed with the actuation of the information control program while allowing specific information to be reduced from among information in the display information storage part 11 of a navigation system. Display areas are selected arbitrarily or automatically from all indicatable kinds and displayable objective background information at the time of the stop according to speed levels. Moreover, a safety driving can be secured by allowing the display information amount to be reduced in accordance with the raising of the speed level.