To provide a wood crusher capable of enhancing the removing workability of bitten foreign matter while keeping a crushing treatment efficiency.

This wood crusher is equipped with a crushing rotor 61 having crushing bits 65 arranged to its outer peripheral part, the first anvil 62 provided on the outer peripheral side of the crushing rotor 61, the first screen 69 provided on the downstream side in the rotary direction of the crushing rotor 61 of the first anvil 62 and arranged so as to leave a gap with respect to the crushing rotor 61, a support frame 125 which supports the first anvil 62 and the first screen 69 and is provided in a revolvable manner so that the first screen 69 is retracted along with the first anvil 62 when an overload acts on the first anvil 62 and a shear pin 77 connected to the support frame 125 and permits the support frame 125 to be retracted from an installation position by the overload acting on the first anvil 62.