To provide a display method for congestion condition which makes variable the time interval for congestion information for display on a screen, in display for the change of a congestion condition with the lapse of time by screen-displaying the congestion information in every time interval provided by road traffic information or the like.

In this display method, a change amount of a congestion distance is calculated in each congestion section on a road (step S2), whether the change amount of the maximum congestion distance is more than a prescribed value or not is determined (step S4, S5), and a set value for the time interval for the congestion information displayed on the screen is changed based thereon (step S6, S7). The set congestion information in every time interval is read out (step S9) to display the congestion condition by change-over (step S10). In this way, an image is screen-displayed to show the change of the congestion condition with the lapse of time.