1. An automotive radar monitor system which comprises, in combination: front monitor radar means for detecting a vehicle interval and relative velocity with an object in the front at any given moment; rear-left and rear-right monitor radar means for detecting a vehicle interval or intervals at any given moment with an object in the front, or an object or objects in the rear, left and/or right with respect to a vehicle in question provided with said system, respectively; channel switching means for processing detection signals from said front and rear radar means in a time-division manner; signal processing circuit means for obtaining an appropriate vehicle interval at a given moment in terms of the travelling speed of said vehicle and relative velocity with said front object at that moment so as to compare said appropriate vehicle interval with an actual vehicle interval with said object at that moment, thereby to output a warning signal relating to said vehicle interval, and for providing signals indicating an attitude of approach of an object or objects in the rear left and/or right at any given moment; and display means for indicating a warning in an integrally simulated fashion as to a vehicle interval with said front object at any given moment and as to the state of approach of a rear object or objects with respect to said vehicle in question at any given moment.