Abstract: When the aircraft flies at a high angle of attack, the flow field on the leeward surface of the slender body evolves in a complicated manner, and asymmetric vortices appear, generating random lateral forces, which greatly affect the maneuverability and agility of the aircraft. In order to solve this problem, a sliding discharge plasma actuator with an along-stream layout was used to conduct wind tunnel experiments on a slender body model, combined with pressure measurement and particle image velocimetry（PIV）. The experimental results show that the actuation voltage of 10 kV is the threshold voltage at which the flow control starts to take effect. When the velocity of the incoming flow is 10 m/s（Re=0.8×10⁵）, the angle of attack is 45°, and the actuation voltage is 16 kV, the best flow control effect can be achieved at the normalized pulse frequency of 1.96, the lateral force coefficient can be reduced by 83.48%. However, as the flow velocity increases, the flow control effect becomes weaker gradually and is expected to disappear at 26 m/s.