Path planning is a core problem of the mobile robot navigation technology. However, few path plan methods that have been proposed consider the path smoothness and the robot attitude in the path. In this paper, a novel path planning method is proposed which considers three optimizing targets, including the path length, the path smoothness and the distance between the path and the obstacles. Firstly, a localization method which the path planning method relies on is explained. Secondly, a path planning model considering the path smoothness and the robot posture is discussed in detail. Thirdly, a solution based on particle swarm optimization (PSO) algorithm is discussed. Fourthly, simulation results are shown and analyzed. At last, conclusion and future work are provided.