This paper proposes a novel control strategy for improving vehicle handling and stability by integrated controlling yaw rate and sideslip angle. Therefore, a T-S fuzzy robust controller is intended to maintain both of the objectives. During normal driving situations, steerability enhancement is the main control objective. However, when the vehicle reaches the handling limits, the controller is involved to ensure vehicle stability. In this controller, the weight between yaw rate and sideslip angle is changing simultaneously according to the estimation of cornering stiffness. A Luenberger observer is intended to identify the tire cornering stiffness. Steer-by-wire system is also put in place to improve the performance. The benefit of this method reduces the influence of habitual driving without losing the control of vehicle safety performance. Linear matrix inequalities(LMIs) are the foundation to obtain such a controller. Carsim-Simulink joint simulation results show the effectiveness of the proposed control method under different driving conditions and the results are shown in this paper.