A stacked conduit assembly includes: a conduit part in which a plurality of plate-like parts are stacked and integrated, and a hollow conduit is formed in an inner layer; and a control board to be fastened to the conduit part by a screw. The plate-like parts include a plurality of plate-like parts that respectively form a side wall, an upper face, and a bottom face of the conduit, a pilot hole is formed in a plate-like part that forms the side wall of the conduit, and the screw is a tapping screw that taps by itself in the pilot hole and is fastened. Thus, a stacked conduit assembly that can stabilize a screw engagement state and realize downsizing or thinning of devices and cost reduction can be obtained.