To facilitate setting not only in automatic cutting but also in manual cutting.

A work W is placed on a table 23 which reciprocates in the right and left direction to a sawtooth BS. A cutting positioning device 41 moves forward to almost cross to a cutting line CL of the sawtooth BS in a right angle direction on the table 23 and bumps a reference plane SP of the cutting width positioning device 41 against the rear end of the work W and the work W is clamped by a clamp device 39. The positional relation in dimension between the reference plane SP and the cutting line CL is detected by a clamp position detecting device. When a single product is cut and processed manually, the distance from the reference plane SP to the cutting line CL can be shifted and positioned easily to the desired cutting width of the work W, which is set previously, based on the detected data. Also in the case of automatic cutting, based on the first cutting plane of the work W trimming, the product is automatically positioned to the desired setting value for cutting.