To make a member for pushing up a lamp pin unnecessary, reduce the number of components, make structure simple, and provide electrically stable connection.

A projecting part 6 is formed on a base bottom surface 5a of a single base fluorescent lamp 1. A locking part 7 is projected on the side surface of the projecting part 6. A lamp pin 8 is projected on the outside of the projecting part 6. A housing recess 9 capable of inserting the projecting part 6 is formed in the center of a socket main body 3. An elastic contact locking spring 10 is arranged so as to be capable of rotating on the bottom side of the housing recess 9. The tip of the projecting part 6 is elastically brought into contact with a pushing up spring part 11 of the elastic contact locking spring 10, and the locking part 7 is engaged with a rotating engaging part 14. A locking wall 13 which engages with the locking part 7 and stops drawing out is formed within the housing recess 9. The projecting part 6 of the single base fluorescent lamp 1 is inserted into the housing recess 9 and it is fixed to the socket main body 3 by turning.