An air-conditioning system for a vehicle, comprising: a refrigeration cycle circuit having a compressor that compresses a first cooling medium and a first heat exchanger that exchanges heat between the first cooling medium and external air; a cooling circuit that circulates a second cooling medium (41A, 41 B) to an equipment for electric-powered driving, that is a temperature controlling object, to perform cooling/air-heating of the equipment for electric-powered driving; and a second heat exchanger that exchanges heat between the first cooling medium and the second cooling medium(41A, 41B); a temperature detection unit (62, 63) that detects a temperature of the equipment for electric-powered driving; a controller that controls the refrigeration cycle circuit and the cooling circuit based on a temperature detected by the temperature detection unit (62, 63, 64, 65); characterized in that, the air-conditioning system further comprises, a prediction unit that predicts a forward temperature of the second cooling medium (41A, 41B) based on detected temperature detected by the temperature detection unit (62 - 65), an accelerator pedal depressing amount and the vehicle speed; and a target temperature change unit that changes a target temperature of the second cooling medium (41A, 41B) based on a result of prediction by the prediction unit; wherein the target temperature change unit changes the target temperature to a lower temperature when the accelerator pedal depressing amount is increased, and the controller controls the refrigeration cycle circuit and the cooling circuit to control cooling/air-heating of the equipment for electric-powered driving based on the temperature detected by the temperature detection unit (62, 63) and the target temperature changed by the target temperature change unit. a refrigeration cycle circuit having a compressor that compresses a first cooling medium and a first heat exchanger that exchanges heat between the first cooling medium and external air; a cooling circuit that circulates a second cooling medium (41A, 41 B) to an equipment for electric-powered driving, that is a temperature controlling object, to perform cooling/air-heating of the equipment for electric-powered driving; and a second heat exchanger that exchanges heat between the first cooling medium and the second cooling medium(41A, 41B); a temperature detection unit (62, 63) that detects a temperature of the equipment for electric-powered driving; a controller that controls the refrigeration cycle circuit and the cooling circuit based on a temperature detected by the temperature detection unit (62, 63, 64, 65); characterized in that, the air-conditioning system further comprises, a prediction unit that predicts a forward temperature of the second cooling medium (41A, 41B) based on detected temperature detected by the temperature detection unit (62 - 65), an accelerator pedal depressing amount and the vehicle speed; and a target temperature change unit that changes a target temperature of the second cooling medium (41A, 41B) based on a result of prediction by the prediction unit; wherein the target temperature change unit changes the target temperature to a lower temperature when the accelerator pedal depressing amount is increased, and the controller controls the refrigeration cycle circuit and the cooling circuit to control cooling/air-heating of the equipment for electric-powered driving based on the temperature detected by the temperature detection unit (62, 63) and the target temperature changed by the target temperature change unit.