PURPOSE: To guide to a storage position automatically by making the tip of a ladder approach a target position by manual operation, storing its position by a storage means, and comparing and computing the position of the tip with the storage position.

CONSTITUTION: The tip of a ladder 1 is brought close to a target position by pressing a position storage switch SW1 on an operation panel 7 and operating operation levers 29, 30, 31 manually. A plural number of valves are stored in a position storage section 3 by pressing switch keys, SW4 to SW7, on the panel 7 and displayed in an operation display means 6. When it is moved again after the tip of the ladder is lowered, a switch SW2 on the panel 7 is pressed to change over switches, S1 to S3, and a position comparison means 20 and a speed comparison feedback means 24 are connected. Comparison and operation are done between the storage position to which the tip of the ladder corresponds and current position by the comparison means 20 in a control section 4 by pressing the keys, SW4 to SW7, of the desired storage position number on the panel 7 continuously, and it is guided to the initial position.