To provide a dismantling device for an oil filter or the like suitable for dismantling a used oil filter, spray can, or the like, superseding an oil filter dismantling method using a screw member, easily coping with dismantlement of various oil filters, easily detaching an uncut casing without needing a special detaching means, cutting the oil filter in a desired position and moreover in a plurality of parts, and easily coping with a dismantling method using manual operation or power.

This dismantling device is provided with a chucking device 8 for turnably holding one side end of an approximately cylindrical object to be dismantled, and a cutter device 9 cutting the object to be dismantled 9. The chucking device 8 is provided with a turnable chucking shaft and a plurality of chucking pieces 45 expansible to each other interlocked with the turning displacement of the chucking shaft. The recessed part or outer peripheral surface of the object to be dismantled 9 is held in a freely engaged/disengaged manner through the chucking pieces 45.