To provide an LED unit that can efficiently reducing a thermal load to electronic components mounted on a circuit board.

In the LED unit 1 having an LED 10, the circuit board 20 for mounting the LED 10 and forming a cathode wiring 21 and an anode wiring 22 on it for supplying power to the LED 10, and a housing 30 for storing the circuit board 20, wherein light of the LED 10 is emitted outside the housing 30, the LED unit 1 has a cylindrical metal heat radiation part 60 for surrounding the LED 10 in a cylinder and having a cylindrical shape in which both ends 61 are opened and soldering a mounting side end edge face 62 as an edge face at a mounting side to the circuit board 10 to either the cathode wiring 21 or the anode wiring 22 and forming a notch not to come in contact with each other.