A current sensor includes: plate-shaped bus bars; a magnetic detection portion; and a shell holding the bus bars. The bus bars are arranged in a first direction. At least some of the bus bars have: a first conductor portion extending in the first direction; a second conductor portion connected to one end of the first conductor portion and extending in a second direction crossing the first direction; and a third conductor portion connected to the other end of the first conductor portion and extending in a third direction. The bus bars at least include first and second bus bars adjacent in the first direction, where the width of the first conductor portion is greater than the thickness thereof, and when viewed from the third direction, the first conductor portions of the first and second bus bars are spaced apart from each other by a certain distance in the second direction.