In order to solve the problem of unknown load on A9 actuator when axisymmetric vectoring nozzle is working, a coupling modeling method combining the space kinematics model of axisymmetric vectoring nozzle and the vector deflection CFD model is proposed. Firstly, according to the CFD calculation, the load condition of the nozzle expansion adjusting plate is solved, then the space posture of each adjusting mechanism in the deflection process is determined by the kinematic model. Finally, combined with force analysis and moment analysis, a mechanical model for load analysis of the vector nozzle A9 actuation system is established, and the load condition of the A9 actuator is obtained. The simulation results show that the output force of A9 actuator increases with the increase of the engine working state at the same vector deflection angle, and the output force of A9 actuator increases with the increase of vector deflection angle and shows sinusoidal periodic change with the change of vector azimuth angle. This method can provide a load spectrum for the ground loading test of the vector nozzle actuation system, which has important engineering application value.