As rotor positions have significant effect on aerodynamic characteristics of hybrid configuration Unmanned Aerial Vehicle(UAV), it is necessary to investigate the criteria of rotor positions arrangement. The aerodynamic characteristics of a typical hybrid configuration UAV is analyzed by numerical method. Taking the lift-to-drag ratio and longitudinal static stability as the optimization objectives, a three-factor four-level orthogonal experimental of the chordwise, spanwise and vertical positions of the rotor is designed. The effects of three factors of rotor position are discussed by means of intuitive analysis and computational analysis. The results show that the maximum lift-to-drag ratio of the optimized design parameter combination obtained by the orthogonal test design result is about 2 times larger than that of the initial design parameter combination, and the slope of the pitch moment coefficient curve increases by about 15%. For present configuration, the results show that the effect of factors on the lift-to-drag ratio and the slope of the pitch moment coefficient curve are in a descending order as follows: chordwise, spanwise and vertical positions.