[Problem] To provide a bus bar attachment device and a bus bar attachment method whereby the work of attaching a bus bar to a battery can be done faster and less expensively, and the bus bar can be positioned relative to the battery with high precision. [Solution] A bus bar attachment device (100) comprises a bus bar supply part (120) for supplying a bus bar (70) onto a pallet (110), and a pressing part (130) for causing two adjacent surfaces in the bus bar supplied by the bus bar supply part to hit against two adjacent wall surfaces in a bus bar positioning part (113) of the pallet. The bus bar is supplied by the bus bar supply part to a position where the two surfaces come to face the two wall surfaces in the bus bar positioning part, and the two surfaces are made by the pressing part to hit against the two wall surfaces in the bus bar positioning part to set the position of the bus bar relative to a battery (10C).