The invention relates to a building storehouse for storing bulk grains. The building storehouse comprises a storehouse bottom, a storehouse wall, interlayer storehouse bottom plates, a storehouse top plate, beams, columns, vertically conveying equipment, multi-point unloading conveying equipment, a storehouse-in distributing chute and a storehouse-out chute, wherein the vertically conveying equipment is arranged on the end part of the building storehouse and is used for vertically lifting the grains and conveying the grains to the top of the storehouse; the multi-point unloading conveying equipment is fixed at the top of the storehouse and is connected with the storehouse-in distributing chute; the grains enter the storehouse through the storehouse-in distributing chute passing through each interlayer storehouse bottom plate; the storehouse-out chute is arranged at the interlayer storehouse bottom plate and penetrates through the storehouse wall; most of the grains can flow out of thestorehouse automatically, and the rest of the grains can be taken out of the storehouse by combining a grain elevator with a self-flow pipeline; the storehouse wall adopts a prestressed hollow concrete plate system and comprises a storehouse composite column, a prestressed hollow concrete plate and an external wall; the prestressed hollow concrete plate is laterally placed in the wall to resist the pressure on the grain side; the two ends of the prestressed hollow concrete plate are connected to the composite column; and an air interlayer is formed between the external wall and the prestressed hollow concrete plate to play a role in thermal insulation.