PURPOSE: To reduce the lateral vibration of a mast at the time of traveling without lowering working efficiency by controlling moving speed so that degree of acceleration and deceleration at the time of accelerating and decelerating a traveling crane is lowered as an elevator is positioned higher.

CONSTITUTION: A travelling crane 1 is formed of a base 4, which is provided with wheels 3 to be rolled on a rail 2 laid along an article warehouse, a mast 5 stood on the base 4, an elevator 6 to be elevated along the mast 5, and a fork 7 provided on the elevator 6. Traveling position of the travelling crane 1 and elevating position of the elevator 6 are detected by sensors 21, 22 made of absolute encoder, and input to a control circuit 20. Moving speed of the travelling crane 1 is controlled so that degree of acceleration and deceleration at the time of accelerating and decelerating the travelling crane 1 is lowered as the elevator 6 is positioned higher. Lateral vibration of the mast 5 is thereby reduced, and when the elevator 6 is positioned low, speed of the travelling crane 1 is increased to prevent the lowering of working efficiency.