Taking full advantage of available traffic environment information, making control decisions, and then planning trajectory systematically under structured roads conditions is a critical part of intelligent vehicle. In this paper, a lane-changing decision-making method for intelligent vehicle is proposed based on acceleration field. Firstly, an acceleration field related to relative velocity and relative distance was built based on the analysis of braking process, and acceleration was taken as an indicator of safety evaluation. Then, a lane-changing decision method was set up with acceleration field while considering driver’s habits, traffic efficiency and safety. Furthermore, velocity regulation was also introduced in the lane-changing decision method to make it more flexible. Afterwards, the polynomial trajectory planning method was matched up with this lane-changing decision-making method and simulations based on Matlab/Simulink were finally conducted to verify the method presented in this paper. As the simulation results showed, adopting the lane-changing decision-making method based on acceleration field, the lane-changing measurements such as starting position, span and driving speed can be optimized with driver’s habits involved. At the same time, the vehicle safety can be well ensured.