To provide an arch bridge breaking device capable of securely breaking a bridge in a short time without causing any danger during operation.

A hopper wall swinging means is provided for a hopper disposed below a body container filled with powdery granular material and vertically put in an upright position. The hopper wall swinging means repeatedly applies a force by which the tapering hopper wall inclining obliquely downward is pushed to the inside and a force by which the hopper wall is pulled up to the outside. By the repetition of the force by which the hopper wall is pushed to the inside and the force by which it is pulled up to the outside, an arch bridge in the container can be securely broken in a short time.