PURPOSE: To send out maintenance work indication such as parts replacement and adjustment required parts before getting to grave failure by collecting the supervisory data of an optional elevator by a supervisory program on the supervisory center device side, and performing the automatic diagnosis of even slight abnormality by a failure diagnosis program.

CONSTITUTION: At the preset diagnosis execution timing of a total supervison object elevator device, the supervisory terminal call of this elevator device is performed. In the case of changing the abnormality detecting condition of this elevator device from the supervisory center device 4 side, a change program and data are transmitted to change the abnormality detecting condition of the supervisory terminal of the elevator device. The supervisory data and abnormality data are then transmitted and held. A failure diagnosis program is executed on the basis of the received data, and the existence of abnormality, its cause, or a place with a sign of abnormality and its content are diagnosed. The diagnosis result is automatically communicated/indicated to the maintenance service point of this elevator. Even slight abnormality can be thereby disposed of without being left as it is.