To provide a crusher capable of reducing fracture of fibers of wood and generation of dust, and obtaining crushed materials suitable for recovering and recycling cellulose, etc., from waste wood.

When wood 100, an object to be crushed, is charged through a charge opening 14 in a way that the growth direction of the wood 100 goes along the direction of the rotary shaft 22 of a cutter drum 20, the wood 100 is crushed by hitting a cutter 50 from the trunk direction of the wood 100. That is to say, the wood 100 is crushed from an intersecting direction to the growth direction at right angles so that it may be stripped along annual rings. Furthermore, since the cutter 50 is attached to the cutter drum 20 in a spiral shape, the cutter 50 continuously hits the wood 100 in order. Thereby, the fracture of the fibers of the wood is restricted, crushing itself becomes efficient and the generation of dust is inhibited.