PURPOSE: To provide an oil tank device for a hydraulic elevator which facilitates and ensures confirmation of a mounting position during normal operation and maintenance and inspection of a filter, a shield plate, and a plug, being a mounting device in the oil tank.

CONSTITUTION: Red display and blue display are applied on the upper end surfaces of screw rods 8 and 17 of a filter 7 and a shield plate 16, respectively, being a mounting device in the oil tank 2 of an oil tank device. Further, red display and blue display are also applied in the vicinity of the mounting positions of mounting metals 9 by which the screw rods 8 and 16 are respectively fixed.