When the airfoil oscillates around a certain axis, the CL-αcurve shows hysteresis loop phenomenon, i.e. the lift characteristics obtained from the two directions to the same angle of attack are different. The effects of the pivot location on the small amplitude forced-oscillation airfoil is studied under low Reynolds number in this paper. It is found that the reason that the hysteresis loop of the lift coefficient varies with the angle of attack is mainly due to the change of the phase of the CL-t curve relative to the α-t curve. It is found that the pivot location mainly changes the effective angle of attack of the airfoil, which leads to the decrease of the lift coefficient curve phase. At the same k, the more backward pivot location, the more likely the hysteresis loop is to be counterclockwise. Because of the phase change, the hysteresis loop may become a straight line, as if the hysteresis loop disappears.