This paper proposes a model-based range extension control system for electric vehicles. The proposed system optimizes the front and rear driving-braking force distributions by considering the slip ratio of the wheels and the motor loss. The optimal distribution depends solely on vehicle acceleration and velocity. Therefore, this system is effective not only at constant speeds but also in acceleration and deceleration modes. Bench tests were conducted for more precise evaluation and to realize experimental results with high reproducibility. The effectiveness of the proposed system was verified through field and bench tests.