In order to improve the success rate and safety of the landing mission, this paper studies the mission subject primitives of the carrier helicopter when landing and the American military helicopter flight quality specification ADS-33E, and selects the longitudinal axis’ response type as the attitude command attitude hold (ACAH) response type. Due to the harsh landing environment of the carrier-based helicopter and the combined external disturbances of the ship’s wake, ship motion, deck ground effect, etc., this paper designs a robust controller based on the mixed sensitivity method, which improves the anti-disturbance features and robust performance of the carrier-based helicopter. Finally, this paper verifies the robust controller's anti-disturbance characteristics and attitude command attitude hold (ACAH) control effect through simulation analysis, and conducts flight quality evaluation. The simulation results show that the designed controller has high anti-disturbance characteristics, the helicopter longitudinal control response is ACAH response type, and the flight quality reaches level 1.