Abstract: In order to accurately reflect the material properties under complex loading paths, experts and scholars have continuously explored biaxial tensile test methods in recent years, including the cruciform sample method. However, due to the particularity of the sample, the conventional electro-hydraulic servo testing machine cannot meet its test requirements, so the two-axis four-cylinder electro-hydraulic servo testing machine is used to solve this problem. Because the center position of the sample needs to be fixed during the test, a biaxial PID coordinated loading control technology is designed based on the center position control method. It is verified by experiments that the two-axis four-cylinder testing machine meets the requirements of controllable deviation of the sample center area and ensures the coordinated control of loading.