In the field of aerospace and high-end equipment manufacturing, it is often accompanied by the occurrence of a large value ratio load. In order to monitor its working status, it is necessary to accurately measure the size and direction of large ratio load. In this paper, a piezoelectric force test system is taken as the research object, and a method of rotating simulation loading for dynamometer calibration is proposed. First, based on the principle of force decomposition, combing the principle of deviation between the actual axis and the theoretical axis of the calibration device, the geometric distribution law of lateral combined force with loading azimuth was obtained during the simulated loading process. Aiming at the characteristics of the lateral force fluctuation, a new simulation loading method-rotation simulation loading method was proposed. Finally, a vector force simulation loading experiment was designed. The experiments of non-rotation simulation loading method and the rotation on the test system was carried out and compared. The results show that the rotation load calibration method reduced the lateral total force output error by 18.7%F.S., which verified the feasibility and rationality of the rotation simulation loading method.