The invention relates to an automatic riveting machine for nuts. The automatic riveting machine comprises a machine frame which is provided with a power distribution control box and an operating screen; the power distribution control box is provided with a workbench; the workbench is provided with fixing devices matched with products; riveting devices are arranged above the fixing devices in a matched mode; each fixing device comprises a fixing base which is arranged on the workbench and matched with each product; a feeding block is arranged behind each fixing base and provided with a feeding groove matched with the hole position of each product; the rear portion of each feeding groove is provided with a push rod which is connected with a push block; a push air cylinder is connected to each push block; and the feeding grooves are in butt joint with a vibration feeding disc. According to the automatic riveting machine for the nuts, the products are fixed through the fixing devices, the fixing devices are provided with the feeding grooves matched with the vibration feeding disc for the nuts, the nuts are pushed into the positions matched with the products through the push rods, and then the nuts are riveted to the products through the riveting devices; and the riveting efficiency of the nuts is greatly improved, and the labor intensity is relieved.