Air cylinder positioning and mounting tool

The utility model provides an air cylinder positioning and mounting tool, which belongs to the technical field of air cylinders and comprises a workbench, a plurality of supporting rods are fixedly connected to the upper end of the workbench, a cover plate and a plurality of second electromagnets are fixedly connected to the upper ends of the supporting rods, the second electromagnets are all arranged at the lower end of the cover plate, and the supporting rods are fixedly connected to the upper end of the workbench. When the air cylinder needs to be installed, the air cylinder can be placed on the circumferential inner walls of the two second electromagnets, then the air cylinder can be magnetically adsorbed through the two second electromagnets so as to be fixed, then the two lead screws are rotated so that the two lead screw nuts can move towards the close ends, and the air cylinder can be installed. And the end covers in the two placing cylinders are installed in the air cylinder, so that the installation