PURPOSE: To protect a wire reliably and to facilitate connecting work by leading out a wire from a tube containing the wire through the hollow section of a coupling body and a wire insertion hole to the outside of a coupling body then cutting a contact pin into the wire and connecting the wire conductivity with a connector.

CONSTITUTION: The body 1 of a coupling 1 for wire containing tube is coupled through a screw 10b with a connector 20, where a notched groove 10c for receiving and passing the wire of the wire containing tube is made in the screw 10b. The connector body 21 is provided with a female terminal member 22 which is coupled with the pin 33 of the connector 30 thus establishing electrical connection. A box nut 32 to be coupled with the connector 20 is provided at one end of the connector body 31 in the male connector 30. Since the wires W1, W2 are conducted each other and the wire W1 is kept in perfectly separated condition from the outside, highly durable A and reliable electrical wiring is realized. Furthermore, the wire containing tube and the coupler are coupled/ uncoupled easily, resulting in high work efficiency.