The present invention relates to a curve control system applied to an automobile adaptive cruise control (ACC) system. The curve control system applied to the ACC system comprises a data acquisition module, used for obtaining signals of each sensor from an automobile CAN bus in real time; a front automobile running state judging module, used for judging whether a front automobile is at a state of entering a curve; a vehicle trajectory road curvature calculation module, used for calculating the road curvature of the vehicle trajectory; an effective target selection module, used for screening effective objects ahead; a vehicle highest curve-passing speed calculation module, used for calculating the highest curve-passing speed to which the vehicle can reach at the radius of turning circle of the vehicle; a speed control module, used for performing reasonable control over the vehicle according to the running working condition of the vehicle, to improve the environmental awareness of the ACC system at the curve working condition.