The work aims to study the physical properties of corn stalk and combine theory analysis with process design to create a process route which can achieve industrialized manufacturing of corn stalk crushing process. Based on effectiveness analysis of the ultra-fine pulverization of corn stalk, routes of shearing, extrusion and impaction were determined scientifically. An effective ultrafine grinder featured by high throughput, low consumption and many crushing meshes and meeting fodder requirement of corn stalk was designed comprehensively. The overall scheme of ultrafine grinder for corn stalk superfine was designed. Crushed corn stalk can be used as fodders of livestock and pads of packing. It is significant for improving the use ratio of corn stalk.