To provide a liquid medicine administration device capable of discriminating between failure in a drive mechanism such as a motor and blockage of a circulation portion that forms a flow path. A liquidmedicine administration device 100 according to the present invention stops delivery of liquid from a liquid delivery tube 142 when an output from a rotation detection unit 132 is not included in a detection region; determines that the liquid delivery tube 142 or a cannula 113 and a support member 114 are blocked when the output of the rotation detection unit 132 is included in the detection region in a state in which a motor 136 is rotated in a rotation direction opposite to the direction for the liquid delivery; and determines that a drive mechanism 131 fails when the output is not includedin the detection region.