A cutting apparatus includes a cutting dust collection box that collects cutting dust and a cutting dust guide plate that is disposed on the downstream side in a processing feed direction relative to a chuck table and receives cutting water and the cutting dust that flow to the downstream side after cutting to guide the cutting water and the cutting dust to the cutting dust collection box. A cutting dust breaking unit that breaks the cutting dust into small pieces is disposed at a position onto which the cutting dust that flows from a plate-shaped cover drops over the cutting dust guide plate.