To provide a grain storage method and an insect control method in which pests possible of attaching to grains may be killed or weakened so that proliferation of them may be suppressed without using a repellent agent or an insect repellent.SOLUTION: There is provided a grain storage method including a step of inserting a second bag 20 into a first bag 10 and a step of charging grains to the second bag 20. At least one of the first bag 10 and the second bags 20 comprises a multilayer film having a barrier layer and an inner layer. The multilayer film has an oxygen permeability of 500 cc/m/day/atm or less.SELECTED DRAWING: Figure 1【課題】忌避剤・防虫剤を用いなくても、穀物に付着し得る害虫を死滅又は弱体化させることができ、繁殖を抑制できる、穀物の保存方法及び穀物を害虫から保護する防虫方法を提供する。【解決手段】第１の袋１０内に第２の袋２０を入れる工程と、前記第２の袋２０内に穀物を収納する工程とを含む、穀物の保存方法であって、前記第１の袋１０及び前記第２の袋２０のうちの少なくとも一方の袋は、バリアー層と内層とを有する多層フィルムを含み、前記多層フィルムの酸素透過度は、５００ｃｃ／ｍ２／ｄａｙ／ａｔｍ以下である、穀物の保存方法。【選択図】図１
