The invention relates to a battery box of a storage battery for an agricultural machine, and belongs to the technical field of agricultural equipment. The battery box comprises a box body; a box cover is arranged on the top of the box body; hoisting holes are formed in the two sides of the box cover; the box cover adopts a dual-layer structure, and consists of an upper layer cover plate and a lower layer cover plate; an oblique plane structure is arranged on the periphery of the top of the box body and the peripheries of the upper layer cover plate and the lower layer cover plate; two ventilating grooves are formed in each of the upper layer cover plate and the lower layer cover plate separately; the ventilating grooves in the upper layer cover plate and the ventilating grooves in the lower layer cover plate are formed in a staggered manner; and the ventilating grooves are rectangular holes. The battery box of the storage battery for the agricultural machine adopts the box cover with the two-layer structure, and the oblique plane structure is arranged on the periphery of the top of the box body and the peripheries of the upper layer cover plate and the lower layer cover plate, so that accumulation of dust and other particulate matters can be reduced; by virtue of the ventilating grooves which are formed in the upper layer cover plate and the lower layer cover plate in a staggered manner, the ventilating effect is ensured while possibility of dust and other particulate matters entering the box body is reduced, thereby improving safety.