A package accumulating device that conveys plural bag packages to a predetermined position while performing an accumulating operation that aligns the packages such that parts of each of the packages lie on top of parts of adjacent packages in a thickness direction, the package accumulating device comprising: a first conveyor that comprises a conveyance surface for accumulating the packages, the first conveyor performing the accumulating operation with the conveyance surface; a second conveyor that comprises a conveyance surface, the second conveyor receiving and further conveying a group of the packages aligned by the first conveyor and being moved from the conveyance surface of the first conveyor onto the conveyance surface of the second conveyor; and a control unit that performs switching between a first state in which a downstream end of the first conveyor in a conveyance direction and an upstream end of the second conveyor in the conveyance direction oppose each other when the second conveyor accepts the group of the packages from the first conveyor and a second state in which a position of the upstream end of the second conveyor is lower than it is in the first state with respect to the downstream end of the first conveyor, characterized in that the control unit lowers the upstream end of the second conveyor after a last package of the group of the packages moves from the conveyance surface of the first conveyor onto the conveyance surface of the second conveyor, and wherein in the first state, the conveyance surfaces of the first conveyor and the second conveyor are both inclined, and in the second state, the upstream end of the second conveyor is lowered so that the conveyance surface of the second conveyor becomes horizontal. a first conveyor that comprises a conveyance surface for accumulating the packages, the first conveyor performing the accumulating operation with the conveyance surface; a second conveyor that comprises a conveyance surface, the second conveyor receiving and further conveying a group of the packages aligned by the first conveyor and being moved from the conveyance surface of the first conveyor onto the conveyance surface of the second conveyor; and a control unit that performs switching between a first state in which a downstream end of the first conveyor in a conveyance direction and an upstream end of the second conveyor in the conveyance direction oppose each other when the second conveyor accepts the group of the packages from the first conveyor and a second state in which a position of the upstream end of the second conveyor is lower than it is in the first state with respect to the downstream end of the first conveyor, characterized in that the control unit lowers the upstream end of the second conveyor after a last package of the group of the packages moves from the conveyance surface of the first conveyor onto the conveyance surface of the second conveyor, and wherein in the first state, the conveyance surfaces of the first conveyor and the second conveyor are both inclined, and in the second state, the upstream end of the second conveyor is lowered so that the conveyance surface of the second conveyor becomes horizontal.