Disclosed is a medical liquid meter 10 for use with a medical liquid feeding device 30 including an expandable container 31, an inlet port 32 for supplying a medical liquid into the expandable container 31 therethrough, and a feed duct 33 for feeding to a patient the medical liquid discharged from one end of the expandable container 31. The medical liquid meter 10 comprises a weight-measuring mechanism 1. The weight of the medical liquid feeding device 30 is measured using the weight-measuring mechanism 1 so as to quantify a remaining amount of the medical liquid stored in the expandable container 31.
