Laser cutting apparatus and laser cutting method

A laser cutting apparatus of the present invention comprises: a laser generating device, a luminous source generating device, a photographic device and a control device; and a laser cutting method of the present invention comprising: performing a laser beam by the laser generating device to cut a processing object, so that the processing object is penetrated to form a penetrating path; projecting a light toward the processing object by the luminous source generating device, so a part of the light is projected to the photographic device through the penetrating path; generating a monitoring image with a transmission area by the photographic device through photographing the processing object; receiving a present size of the transmission area from the monitoring image, and comparing the difference between the present size and an objective size; controlling the laser generating device by the control device for continuing or stopping to perform the laser beam. Therefore, the processing object can be accurately pene