The invention relates to the technical field of soybean processing, in particular to a soybean processing pretreatment method. Equipment comprises a seal box, positioning devices, a containing device,a plugging component, a feeding device, a discharging device and a seal plate, the positioning devices, the containing device and the plugging component are arranged in the seal box, the plugging component is arranged at the bottom of the seal box, the containing device is positioned right above the plugging component, two ends of the containing device are connected with the positioning devices,sieve pores are formed in the containing device, the height between the containing device and the seal box can be controlled by the positioning devices, the containing device is abutted to or separated from the plugging component, the inclination angle of the containing device can be adjusted, so that the containing device rotates around an outlet end, and the plugging component is abutted to thecontaining device when the containing device is positioned at the lowest end to solve the problems that existing screening is incomplete, hard grains in soybeans are difficultly treated, and the soybeans absorbing water non-uniformly expand. Therefore, screening effects are complete, and the soybeans absorbing the water more uniformly expand.