Abstract: Provided is a mushroom bed cultivation bag where a bag main body can be surely torn regardless of nonuniformity of a thickness of a filter, a material, and the like. A mushroom bed cultivation bag includes a vertically long bag main body which has an opened upper end and is formed of a plastic film formed by aligning molecules so that tensile strength of a vertical direction is higher than tensile strength of a horizontal direction, and a rupture handle fused with the bag main body at a position that is different from a position of the bag main body, and rupturing the bag main body to tear the bag main body. A fuse portion fusing the rupture handle with the bag main body is formed in a mountain-shape where a tear-initiation side (opening side of an upper end of the bag main body) faces upward.