To analyze the influence of low-level wind shear on the flight characteristics of a large helicopter during takeoff， a wind shear model and a helicopter flight dynamics model coupled with wind interference are established. The effects of vertical shear of horizontal wind with different intensities and directions， as well as vertical shear of upwash and downwash with different intensities， on the attitude， displacement， and control response of a large helicopter during takeoff are simulated. The results show that with the increase of vertical shear intensity of the horizontal wind， the pitch attitude of the helicopter gradually oscillates， and the longitudinal position shifts obviously. The lateral and longitudinal cyclic are significantly affected by the change in wind direction. Both upwash and downwash vertical shears cause changes in helicopter attitude and position， but downwash results in greater attitude variations and has a more serious effect on pilot control.