PURPOSE: To discover oil leakage in an early stage in the case where an operation delay of an oil pressure control valve is caused by detecting whether or not operation of the oil pressure control valve is normal, measuring magnitude relationship between a detected car position movement quantity and a predetermined set quantity, and conducting a post-processing operation in accordance with the judging result.

CONSTITUTION: A car position movement quantity within a counting time of a movement quantity detector 24 and a timer 22 after an elevator stopping command is generated is found by subtracting a detection value at a closing time point of the timer 22 from an initial stage detection value of a car position detector 21. When an output value or an integration value thereof of a motor rotation speed detector 23 up to the closing time point of the timer 22 exceeds a specified value, operation delay of an oil pressure control valve is judged. When the movement quantity is small, it is stored in an oil pressure control valve operation delay small quantity storage counter 26 via a movement quantity-small judging instrument 25. When the movement quantity is large, an elevator start/stop circuit 28 is operated via a movement quantity-large judging instrument 27 so as to conduct preventive maintenance.