Abstract: Disclosed is a damage detection apparatus for use in a sewing machine including a bobbin having a conductive wire wound thereon, and a sewing mechanism having a metal needle, which sews the conductive wire drawn from the bobbin to an object with thread by means of the metal needle. The damage detection apparatus includes a terminal to be electrically connected to part of the conductive wire, and an indicator electrically connected to both of the terminal and the metal needle and arranged to indicate the occurrence of contact of the metal needle with the conductive wire.