To provide a device for laser drilling with which numerous drillings are performed in a shorter time than that of a conventional method of laser drilling.

The device is provided with a uniform optical system 13 which converts a laser beam radiated from a laser head 10 into a laser beam having a linear sectional shape, cylindrical lenses 15, and a driving mechanism which synchronously moves a mask 11 and a printed wiring board 12. The irradiated position with the linear laser beam is fixed, the driving mechanism moves the mask and the printed wiring board in a manner that the mask passes through the irradiated position and its moving direction is perpendicular to the elongated direction of the linear laser beam, and the mask is scanned by the linear laser beam, thus a drilling defined by a mask pattern of the mask is performed on the printed wiring board.