To provide a socket for an inner space illuminating explosion-proof-type lamp not disturbing global environment, capable of freely exchanging an electric bulb.

The electric bulb socket is composed of a socket main body 3 with a sealed bottom part, and an electric bulb base receptacle 4 fitted in close contact inside the main body. The socket main body 3 and the electric bulb base receptacle 4 are made of electric insulation material not generating halogen at burning. A screw part 8, into which an electric bulb base 21 is screwed is provided.