Abstract: A four-wheel drive system with boosting operation includes: a battery; a voltage boosting device; a front wheel drive unit connected parallel to the battery via the voltage boosting device and including a first motor generator and a first inverter; and a rear wheel drive unit connected parallel to the battery bypassing the voltage boosting device and including a second motor generator and a second inverter. An output power of front wheel drive unit is higher than an output power of rear wheel drive unit, and the output power of rear wheel drive unit is higher than a boosted output power of voltage boosting device. The control method of four-wheel drive system with boosting operation includes controlling the front and rear wheel drive units such that an output power flowing through the voltage boosting device does not exceed a rated boosted output power of voltage boosting device.