Hydrostatic bearings are widely used in the spindle of precision and high-speed gear shaper machine tools due to its high rotational accuracy and oil film stiffness,but the heat generated by the reciprocating movement of the spindle and the periodic change of the lateral force of the ball tie rod on the spindle will lead to changes in the stiffness of the hydrostatic oil film,thus the processing accuracy will be affected.Aiming at the insufficient stiffness of the hydrostatic pressure spindle of the large tooth width and long stroke gear shaper YKW51160,the finite element analysis model of oil film was established.The structural optimization design schemes 〖JP2〗of the hydrostatic pressure oil chamber edge chamfering and the rectangular-ambulatory-plane oil chambers were used to improve the stiffness and bearing capacity of the hydrostatic pressure oil film.The bearing capacity and oil film stiffness of the optimized hydrostatic pressure bearing were analyzed and verified based on the fluid-structure coupling method.The simulation and example calculation results show that the optimized bearing capacity and oil film stiffness can be increased by 12% and 12.3% at the maximum,which meets the bearing capacity and oil film stiffness requirements required for the radial periodic impact of the connecting rod on the spindle.