Ajoint connector (10, 110) comprising: a connector housing (11, 111) that defines a fitting space (12, 112) for a mating connector (30, 130) by a back wall (11a, 111a) and a hood wall (11b, 111b) extending forward from the back wall(11a, 111a); a circuit board (5, 105) that is fixed to a housing body to which the connector housing (11, 111) is detachably attached, and that is located behind the back wall (11a, 111a) of the connector housing (11, 111) through a component space (6, 106) when the connector housing (11, 111) is attached to the housing body; an independent terminal (15, 115) in which a terminal portion at a distal end penetrates the back wall (11a, 11 1a) of the connector housing (11, 111) and protrudes into the fitting space (12, 112a) to serve as a connector terminal when a proximal end is joined to a circuit conductor of the circuit board (5, 105) and the connector housing (11, 111) is attached to the housing body; a relay terminal (15, 118), characterized in that: the relay terminal (15, 118) has a proximal end joined to the circuit conductor of the circuit board (5, 105); and the joint connector (10, 110) further includes a joint terminal (17, 117) including: a bridge portion (17c, 117c) fixed to the back wall (11a, 111a) of the connector housing (11, 111); a plurality of terminal portions (17a, 117a) extending forward from the bridge portion (17c, 117c) in a state of being conductive to each other by the bridge portion (17c, 117c) and protruding into the fitting space (12, 112) of the connector housing (11, 111) to serve as connector terminals; and one contact conduction piece (17b, 117b) that extends from the bridge portion (17c, 117c) to the back of the back wall (11a, 111a) of the connector housing (11, 111) and is elastically brought into conductive contact with the relay terminal (15, 118) via an elastic deformation portion (18, 118a) when the connector housing (11, 111) is attached to the housing body. a connector housing (11, 111) that defines a fitting space (12, 112) for a mating connector (30, 130) by a back wall (11a, 111a) and a hood wall (11b, 111b) extending forward from the back wall(11a, 111a); a circuit board (5, 105) that is fixed to a housing body to which the connector housing (11, 111) is detachably attached, and that is located behind the back wall (11a, 111a) of the connector housing (11, 111) through a component space (6, 106) when the connector housing (11, 111) is attached to the housing body; an independent terminal (15, 115) in which a terminal portion at a distal end penetrates the back wall (11a, 11 1a) of the connector housing (11, 111) and protrudes into the fitting space (12, 112a) to serve as a connector terminal when a proximal end is joined to a circuit conductor of the circuit board (5, 105) and the connector housing (11, 111) is attached to the housing body; a relay terminal (15, 118), the relay terminal (15, 118) has a proximal end joined to the circuit conductor of the circuit board (5, 105); and the joint connector (10, 110) further includes a joint terminal (17, 117) including: a bridge portion (17c, 117c) fixed to the back wall (11a, 111a) of the connector housing (11, 111); a plurality of terminal portions (17a, 117a) extending forward from the bridge portion (17c, 117c) in a state of being conductive to each other by the bridge portion (17c, 117c) and protruding into the fitting space (12, 112) of the connector housing (11, 111) to serve as connector terminals; and one contact conduction piece (17b, 117b) that extends from the bridge portion (17c, 117c) to the back of the back wall (11a, 111a) of the connector housing (11, 111) and is elastically brought into conductive contact with the relay terminal (15, 118) via an elastic deformation portion (18, 118a) when the connector housing (11, 111) is attached to the housing body. a bridge portion (17c, 117c) fixed to the back wall (11a, 111a) of the connector housing (11, 111); a plurality of terminal portions (17a, 117a) extending forward from the bridge portion (17c, 117c) in a state of being conductive to each other by the bridge portion (17c, 117c) and protruding into the fitting space (12, 112) of the connector housing (11, 111) to serve as connector terminals; and one contact conduction piece (17b, 117b) that extends from the bridge portion (17c, 117c) to the back of the back wall (11a, 111a) of the connector housing (11, 111) and is elastically brought into conductive contact with the relay terminal (15, 118) via an elastic deformation portion (18, 118a) when the connector housing (11, 111) is attached to the housing body.