The invention discloses a method for reducing organophosphorus pesticide residues in soybean milk, which belongs to the technology field of food safety. The soybean milk containing the organophosphorus pesticide residues flows into a pretreatment chamber by a peristaltic pump; degassing and precooling are applied to the soybean by using a vacuum pump for vacuum pumping; high voltage pulsed electric field parameters are set; a peristaltic pump is started and then high voltage pulsed electric field treatment is carried out on the soybean milk after being pumped into a high voltage pulsed electric field treatment chamber; a storage bottle is used for receiving the treated soybean milk at the outlet end of the treatment chamber. The soybean milk is treated by high voltage pulsed electric field technology and the concentration of the organophosphorus pesticide residues of the soybean milk is obviously dropped. Besides, the temperature of the soybean milk in the whole process of the treatment is not higher than 50 DEG C, which exerts no obvious influence on the nutrition and sensory quality of the soybean milk, in addition, a dual function of non-thermal sterilization and the degradation of pesticide residue can be realized. The method can be promoted to the degradation of organophosphorus pesticide residues in other liquid foods.