Provided is a cutting device electrically connectable to a conductive wire of a conductive-wire mounted package provided with the conductive wire that allows for electric current to flow to the package with a drug housed therein to detect a change in current flowing state of the conductive wire which is cut along with discharging of the drug from the conductive-wire mounted package. The detecting device includes a holding part configured to hold therein the conductive-wire mounted package and electrically connectable to the conductive wire. The holding part includes a pair of holding pieces that are movable toward and away from each other, and a positioning structure that is provided in at least one of the pair of holding pieces to position the conductive-wire mounted package relative to the holding part.