To provide a lighting device excellent in heat radiation which efficiently radiates heat at the time when the lamp module is lighted.

The lighting device comprises a lamp module 300 equipped with LED elements on the surface of a substrate 310 and a socket 200 which has a receiving port 211 for receiving the lamp module 300 on the front surface side. A receiving bottom 210a of the socket 200 for receiving the lamp module 300 has a nearly same plane shape as the rear face of the substrate 310 of the lamp module 300, and the socket 200 is equipped with a power feeding terminal 220d which presses the lamp module 300 to the receiving bottom 210a when the lamp module 300 is rotated with an axis of a direction parallel to the receiving direction in the state it is received through the receiving port 211.