Since buses need to stop at harbor-shaped stops for passengers to get on and off the vehicles, the cur- vature of the lane change curve at the final stop point is not zero but approximate to zero. In lane changing tra- jectory planning algorithms, lane changing target position has been given artificially. Due to the complex urban traffic environment, there is a great deal of uncertainty, which affects the accuracy of the final trajectory curve. To solve the problem, this paper obtained the data of the actual lane changing trajectory through field investiga- tion. Based on the linear functional lane changing trajectory model and sine functional lane changing trajectory model, and combined with the multivariate linear models of lane changing time, bus entry speed, spare berth number as well as longitudinal distance of lane changing, an optimized lane changing trajectory model for bus arrivals of harbor-shaped stop was proposed. With the given evaluation parameters of the lane changing trajecto- ry, the lane changing trajectory from this optimization model was calculated by means of Matlab simulation test. Comparison between the lane changing trajectory curve and lane changing trajectory curve based on the sine functional lane changing trajectory model as well as the bus lane changing trajectory in the actual situation was made. The simulation results show that this optimization model is feasible and effective.