With the rapid development of the machinery manufacturing industry,the specifications of horizontal milling and boring machines in various fields are increasingly demanding,so its vertical drive system must be redesigned,calculated and checked.According to the needs of a user’ s large horizontal milling and boring machine,the vertical drive system was redesigned,and the triple brake mechanism was proposed for the spindle box weighing up to 8 000 kg to achieve locking,and the counterweight balance was achieved by using the cylinder with the accumulator.The calculation and verification of important parameters and indicators such as motor torque,speed,inertia,lead screw load,life and stiffness were calculated and verified.The drive system has been put into production,the prototype runs smoothly.