The present invention aims to provide a liquid medicine administration device capable of obtaining a residual amount of a liquid medicine remaining in a living body of a user in consideration of an activity of the user, and administrating an appropriate delivery amount of a liquid medicine based on of the residual amount.The liquid medicine administration device includes a liquid delivery unit 100 that delivers a liquid medicine into a living body, a first control unit 260 that controls liquid delivery operation of the liquid delivery unit, an activity detection unit 60 that detects an activity based on a motion of a body of a user, a second storage unit 51 that stores already-delivered liquid data relating to a delivery amount of the liquid medicine delivered by the liquid delivery unit into the living body, and a calculation unit 261 that calculates a residual amount of the liquid medicine in the living body on the basis of the already-delivered liquid data stored by the second storage unit and the activity detected by the activity detection unit, and calculates a scheduled delivery amount of the liquid medicine to be administered to the living body on the basis of the residual amount of the liquid medicine. In addition, the first control unit controls the liquid delivery operation of the liquid delivery unit so that the scheduled delivery amount of the liquid medicine is delivered to the living body.