The FE models of the front beam and the moving trolley of pipe hydrostatic tester are built with FE simulation software ABAQUS in the study. With the FE models, the force statuses of the two heavy parts of pipe hydrostatic tester are studied. It is found that the stress of the action field of the axial force and that of small field contacting with the pins of the front beam is higher and thicker middle cylinder can significantly improve the stress of the front beam. The stress of the middle cylinder and that of small field contacting with the pins of the moving trolley is higher. Thicker middle cylinder and optimizational ribs can significantly improve the stress of the moving trolley. The front beam and the moving trolley are optimized and the strength and the stiffness of the optimized front beam and moving trolley can be satisfied with the requirement of application. The results of the study are very useful to design the pipe hydrostatic tester.