To provide a medical liquid administration device capable of discriminating between failure of a drive mechanism such as a motor and blockage of a flowing portion forming a flow path.A medical liquid administration device 100 according to the present invention stops liquid feeding from a liquid feed tube 142 when an output from a rotation detection unit 132 is not included in a detection region, determines occurrence of blockage in the liquid feed tube 142 or a cannula 113 and a support member 114 when the output from the rotation detection unit 132 is included in the detection region with a motor 136 rotating in a reverse rotation direction to that during the liquid feeding, and determines occurrence of failure in a drive mechanism 131 when the output is not included in the detection region.
