The invention belongs to the technical field of grains storage and relates to a method for manufacturing grain insect expelling bags. The method comprises weighting dry argy wormwood leaf stems, willow leaves, perillaseed leaf stems, chrysanthemum leaf stems, dry red peppers and dry kelp, cutting the plant materials into sheet geometrical shapes, mixing and drying the materials to obtain a plant mixture, smashing the plant mixture, and stirring the plant mixture in a container to obtain a plant mixed powder; weighing the dry red pepper according to the plant mixed powder material weight ratio, adding water which is 5 times of the weight of the dry red peppers and heating and boiling the mixture, keeping the mixture away from fire and cooling the mixture to the room temperature, submerging non-woven bags or gauze bags in dry red pepper water for half an hour, taking out and drying the non-woven bags or the gauze bags, filling the material plant mixed powder in the non-woven bags or the gauze bags submerged in the dry red pepper water, and sealing the bags to obtain the grain insect expelling bags. According to the method, the design principle is simple, the bags are made of pure natural plant mixtures and have no toxic and side effects on human bodies, the manufacture cost is low, the manufacture principle is simple, and the method is safe and environmentally friendly.