The rotating electrical device has a motor, a bearing holder, and a busbar unit. The busbar unit has a plurality of busbars, and an electrically insulating busbar holder enclosing the plurality of busbars. The plurality of busbars are electrically connected to the plurality of coils, respectively, and inserted, on the bearing holder side of the busbar holder, through each of the plurality of terminal through-holes in the bearing holder, and the busbar holder is configured to enclose the periphery of a part where the plurality of busbars are inserted through the terminal through-holes.