1. An abnormality diagnosis device comprising: an abnormality diagnosis unit which carries out abnormality diagnosis on the basis of sensor data measured by sensors attached to each part of a machine; a storage unit which, if an abnormality is found, stores the sensor data thereof; an abnormality diagnosis data gathering unit which sends abnormality diagnosis data to a data center using communication; and a unit which predicts an available capacity run-out date on which a storage device of the machine runs out of remaining available capacity when the communication state is not good and not all unsent sensor data can be sent to the data center.