A vehicle control device of a vehicle, the vehicle comprising an engine, a battery chargeable with electric power generated by a generator driven with power of the engine, and two or more air conditioner units (74f, 74r) operable with electric power of the battery, the vehicle control device comprising: a power consumption prediction device that predicts an amount of electric power consumed by a vehicle; an idle reduction controller that performs idle reduction control of the engine; an SOC detector that detects a state of charge of the battery; a power amount setter that sets during running of the vehicle an amount of power for idle reduction, which is predicted to be used during a stop and start period from an engine stop to an engine restart by the idle reduction control, based on the power consumption of the air conditioner units (74f, 74r) predicted by the power consumption prediction device; and an SOC controller that controls charging of the battery with the electric power of the generator during running of the vehicle to prevent a remaining amount of power as a difference between the SOC detected by the SOC detector and a lower limit of an available SOC range from decreasing below the amount of power for idle direction; wherein the power consumption prediction device comprising: a passenger count detector that detects count of passengers in the vehicle; an active air conditioner unit count detector that detects a count of active air conditioner units in the vehicle; a vehicle interior temperature detector that detects a vehicle interior temperature of the vehicle; an air conditioner unit set temperature acquirer that obtains a set temperature of each of the air conditioner units (74f, 74r); and a power consumption predictor that predicts power consumption of the air conditioner units (74f, 74r) during idle reduction of the engine, the predicting power consumption being performed when the vehicle is running prior to the idle reduction, by using the count of passengers, the count of active air conditioner units (74f, 74r), the vehicle interior temperature and the set temperature of each air conditioner unit; wherein the SOC controller is configured to: ( a) calculate a level of a vehicle state based on the predicted power consumption of the vehicle; (b) calculate a driving environment index using at least one of: (i) a calculated vehicle stop time rate of the vehicle during a predetermined latest time period; and (ii) at least one of a vehicle average speed, an acceleration and a frequency of gearshifts of a transmission; and (c) calculate an SOC target value using the level of the vehicle state and the driving environment index to control charging of the battery with the electric power of the generator. a power consumption prediction device that predicts an amount of electric power consumed by a vehicle; an idle reduction controller that performs idle reduction control of the engine; an SOC detector that detects a state of charge of the battery; a power amount setter that sets during running of the vehicle an amount of power for idle reduction, which is predicted to be used during a stop and start period from an engine stop to an engine restart by the idle reduction control, based on the power consumption of the air conditioner units (74f, 74r) predicted by the power consumption prediction device; and an SOC controller that controls charging of the battery with the electric power of the generator during running of the vehicle to prevent a remaining amount of power as a difference between the SOC detected by the SOC detector and a lower limit of an available SOC range from decreasing below the amount of power for idle direction; wherein a passenger count detector that detects count of passengers in the vehicle; an active air conditioner unit count detector that detects a count of active air conditioner units in the vehicle; a vehicle interior temperature detector that detects a vehicle interior temperature of the vehicle; an air conditioner unit set temperature acquirer that obtains a set temperature of each of the air conditioner units (74f, 74r); and a power consumption predictor that predicts power consumption of the air conditioner units (74f, 74r) during idle reduction of the engine, the predicting power consumption being performed when the vehicle is running prior to the idle reduction, by using the count of passengers, the count of active air conditioner units (74f, 74r), the vehicle interior temperature and the set temperature of each air conditioner unit; wherein ( a) calculate a level of a vehicle state based on the predicted power consumption of the vehicle; (b) calculate a driving environment index using at least one of: (i) a calculated vehicle stop time rate of the vehicle during a predetermined latest time period; and (ii) at least one of a vehicle average speed, an acceleration and a frequency of gearshifts of a transmission; and (i) a calculated vehicle stop time rate of the vehicle during a predetermined latest time period; and (ii) at least one of a vehicle average speed, an acceleration and a frequency of gearshifts of a transmission; and (c) calculate an SOC target value using the level of the vehicle state and the driving environment index to control charging of the battery with the electric power of the generator.