Local path planning emphasizes generating a drivable path in micro traffic scenarios, which requires high safety and comfort for each discrete point along the path. At present, few local path planning methods consider physical characteristics such as continuity of path curvature and constraints on the starting and ending points of the path. In this study, a lane-changing decision and planning method based on a safe lane-changing domain is explored. A critical safe lane-changing angle model is established for typical lane-changing scenarios, and for lane-changing scenarios involving dual obstacles that cannot evolve into single-obstacle lane-changing scenarios, a safe lane-changing domain is established. Several commonly used lane-changing paths are compared, and the B-spline curve method is selected as the local path planning method. The optimal lane-changing path based on the safe lane-changing domain is determined using the lane-changing time and the average curvature of the lane-changing path. A lane-changing decision strategy based on the safe lane-changing domain is proposed. Simulation verification of the proposed lane-changing strategy is realized in typical lane-changing scenarios by using the Simulink and PreScan computing platforms. The results show that the proposed lane-changing decision and lane-changing path planning can achieve a safe lane change for the ego vehicle.