In order to solve the problem that the rotor is working on the high total collective state during high-speed high-altitude heavy load flight of helicopter， which is more prone to stall and leads to a significant increase in control system load， a rotor plateau aerodynamic design method based on load divergence control is proposed. In traditional helicopter rotor design， helicopter performance， noise， and empty weight control are common design goals. The problem of root stall， which has litter impact on the rotor thrust， is often ignored， but it has a significant impact on plateau helicopter. The rotor dynamics model is constructed， and is used to calculate the variation curve of the dynamic aerodynamic moment coefficient C_m with thrust coefficient per solidity C_T/σ. Then the C_m gradient point on the curve is used as the basic criterion for the rotor stall. The C_m gradient points under different forward ratio μ are analyzed， and the C_T/σ envelope of the rotor stall load divergence is formed， which is one of the design boundaries of the plateau rotor. The theoretical analysis and flight test results of helicopter designed by using this method， such as the AC313 large civil helicopter， show that it can greatly reduce the risk of rotor stall in typical flight mission at high altitudes， effectively control the load of the rotor control system， increase the service life of the control system， improve the flight comfort， and greatly ensure flight safety， which is of great significance to the entire life of helicopter.