The influences of disturbing gravity on trajectory can′t be ignored when the missile is gliding at supersonic speed in near space.A three degree-of-freedom trajectory model was established considering the earth′s flattening factor and rotation.The disturbing gravity is calculated by using the spherical harmonic function method, and the variation tendency of the disturbing gravity and the landing point deviation under different-order coefficient are analyzed for the skipping-gliding trajectories with fixed-initial flight height and speed.At the same time, under the fixed-order disturbing gravity, the influence of disturbing gravity on the accuracy of the landing point under different shooting angles and different initial flying heights of skipping-gliding trajectory is analyzed respectively.The simulation results show that:1) The maximum deviation of the drop point caused by the disturbing gravity under different shooting angles of skipping-gliding trajectory is more than 4900 meters, and the deviation decreases with the reduction of the initial height of the ballistic trajectory;and 2) When the order of the disturbing gravity exceeds 360, the drop point deviation tends to be consistent, and the calculation results are reliable.Therefore, under the actual combat background, it is necessary to consider the influence of disturbing gravity on the hitting precision of the missile.Under the condition of meeting the operational requirements, it is possible to reduce the initial height of the skipping-gliding trajectory to reduce the impact of the disturbing gravity on the precision of the landing point.