An imaging unit includes: a semiconductor package having an image sensor and having a first connection electrode on a back face thereof； a first multi-layer substrate having layered substrates and having second and third connection electrodes respectively on front and back faces of the first multi-layer substrate, the second connection electrode being configured to be connected to the first connection electrode； a second multi-layer substrate having layered substrates, the second multi-layer substrate being configured to be connected to the back face of the first multi-layer substrate such that a layer direction of the second multi-layer substrate is perpendicular to a layer direction of the first multi-layer substrate； an electronic component mounted inside the first multi-layer substrate； and cables configured to be connected to the second multi-layer substrate. The first and second multi-layer substrates lie within a projected plane in an optical axis direction of the semiconductor package.
