To provide coil units, electronic instruments and the like, which can radiate heat generated in a coil into a space outside a protective member, while the number of components does not increase.
A coil unit 100 has a coil 110, and a protective member 120 that contacts a transmission surface of the coil 110 and covers at least the side of the transmission surface of the coil 110. The protective member 120 is composed of a resin material with an inorganic material added therein. The protective member 120 is also used as a heat radiation plate that dissipates heat generated in the coil 110 and radiates the heat.