To provide an apparatus and method for automatically inserting a belt sleeve by bringing a center of a shaft of a working unit in an open state into coincidence with that of the sleeve, conveying the sleeve in the state that the centers coincide, and automatically inserting it into the shaft of the working unit.

A limit switch 3 of a first sensing means descends at the same distance as a distance for a photoelectric sensor 4 of a second sending means to ascend until the sensor 4 senses a lowermost end of the belt sleeve by using a hydraulic cylinder 17. Then, a toothed belt 7 coupled to a first elevating means 6 descends the switch 3 at the same distance as an ascending distance of the sleeve 2 simultaneously when the sleeve 2 ascends by the elevating means 6. And, when the switch 3 is brought into contact with an uppermost end of the sleeve 2, ascending of the sleeve 2 is stopped, and the sleeve 2 is brought into coincidence with a central position of a shaft of a working unit.