The aerodynamic performance of Flapping-wing Micro Air Vehicle (FMAV) is dependent on the motion of flapping wings completely. The kinematics of flapping-wing can mainly be divided into plunging, pitching and swing, representatively. The swing effects on the aerodynamic performance of flapping-wing in “0”-figure and “8”-figure wingtip path are studied quantitatively in this paper by solving the RANS equations. According to the numerical results, the pitching motion can increase the lift and the thrust forces simultaneously. The swing can mainly increase the lift force, also increase the drag force a little. The “8”-figure swing motion increase the lift and the drag forces more than the “0”-figure swing motion. The result of this paper suggested that the pitching is a good manner to increase the thrust and the swing is a good manner to increase the lift, especially the “8”-figure swing can increase the lift notably.