To provide a control method capable of performing leveling work by transversely operating an excavating part at a suitable transverse feeding speed according to the strength of the excavating part and capable of preventing stop of an unloader caused by excessive load by improving the operating efficiency and preventing excessive force from being applied to the excavating part.

In the method for controlling an unloader for lifting loads by scraping loads by means of an excavating part mounted on the lower part of a bucket elevator column 1 and for continuously rotating a plurality of buckets 12a, force to be longitudinally applied to the excavating part is detected by a sensor provided on the bucket elevator column 1 and compared with preset force, and the speed for transversely feeding the excavating part is set to the suitable speed.