Aiming at the failure of steering system, a fault-tolerant control strategy based on torque allocation is proposed. A two-point preview model is established to derive the desired steering wheel angle according to the required vehicle motion. Using the two-degree-of-freedom vehicle model, the yaw angular velocity and the sideslip angle of the target body are further obtained. The yaw moment is obtained by sliding mode control, and the fault-tolerant control is realized by the torque allocation strategy. In order to verify the proposed fault-tolerant control strategy, simulation results show that car’s angular velocity is very consistent with the desired yaw angular velocity, that the proposed algorithm can effectively deal with steering faults of steering-by-wire vehicle,and that it has a certain engineering practicability.