The utility model relates to a secondary cable inspection of a line auxiliary device, its technical characterstic lies in: including hollow cylinder shape insulating casing, electric test line plug, ametallic disc, conductive spring, the 2nd metallic disc and metal probe, axial system has the cavity in hollow cylinder shape insulating casing, the cavity is made by the cylindrical cavity of upperend and tubaeform cavity an organic whole of lower extreme, electric test line plug inlays the dress on cylindrical cavity inner wall upper portion, its lower extreme with a metallic disc's last surface geometry center links firmly, a metallic disc's lower surface center with conductive spring's one end is connected, and this conductive spring's the other end and the 2nd metallic disc's last surface geometry center link firmly, the 2nd metallic disc's lower surface center with the solid be connected together of metal probe, this metal probe downwardly extending arrive the bottom of tubaeform cavity. The utility model discloses can draw testing terminal metal end connector for the reserve core of not unidimensional cable.