Abstract: With the continuous improvement of aero-engine performance requirements, the environmental temperature requirements of engine actuator products are constantly increasing. In this paper, taking the typical aero-engine vector nozzle actuator products as the research object, research on thermal design technology of vector nozzle actuator is carried out. According to the external thermal environment of the actuator, the corresponding active cooling and heat dissipation design is carried out. The cooling effect of the cooling structure and the influence of the cooling flow rate on the temperature distribution of the actuator are studied. At the same time, the thermal environment test of the actuator is carried out, and the results of simulation and test are compared and analyzed, which verifies the rationality of the active cooling structure and provides certain reference and guidance for design of the similar actuator cooling structure and system.