Provided is a current detection device capable of reducing manufacturing cost. A current detection device 1 includes a plate-like bus bar, a printed circuit board on which a magnetic field detecting element is mounted, a magnetic member, and a housing holding these components. The bus bar can be assembled into the housing by sliding in its longitudinal direction. The housing includes a first rib pressing the bus bar to restrict a movement in a thickness direction of the bus bar, a second rib pressing the bus bar to restrict a movement in a width direction of the bus bar, and a retaining protrusion fitting into a cutout portion provided at both sides in a width direction of the bus bar so as to retain the bus bar in a longitudinal direction of the bus bar.