In order to satisfy the design requirements of Lane Keeping Assistance System (LKAS), a driver steering override (DSO) strategy is necessary to deal with the driver’s interaction with the system. And the system can be overridden by the strategy in case of lane change, obstacle avoidance and some other emergencies. However, evaluation and optimization of the DSO strategy for LKAS cannot easily be completed quantitatively in consideration of driver’s acceptability due to the lack of a reliable process. In this research, firstly, subjective and objective evaluation experiment is designed. To be specific, for the objective evaluation experiment, several objective characteristic indices (CI) are extracted to describe the outward performance of DSO strategy such as the steering hand torque instead of using the parameters from a certain type of controller. As for the subjective evaluation experiment, the initial questionnaire consisting of subjective evaluation items is designed and then it is simplified by correlation analysis between its items based on pre-experiment results to eliminate information redundancy. Additionally, proper weights are given to different items of the questionnaire by using Analytic Hierarchy Process (AHP), and driver’s comprehensive evaluation of DSO strategy is added by this method. Secondly, correlations between the subjective and the objective evaluation results are established using regression method. Finally, the optimal performance of DSO strategy is acquired by setting the desired comprehensive evaluation ratings as the optimization goal, which is based on the correlations established previously. Overall, with the utilization of the newly designed experiment, it would be possible to achieve the following four advantages: generic objective evaluation regardless of different controllers, reliable comprehensive subjective evaluation, less subjective evaluation experiment time and the optimization of DSO strategy for LKAS in consideration of driver’s acceptability. Moreover, acquired optimal outward performance can be used for different type of controller design.