The laser machining method for machining through holes with a laser in a workpiece in which an insulating layer is sandwiched between a first conductor layer and a second conductor layer is provided with: a reference through hole-forming process for irradiating a laser on the workpiece from the first conductor layer side while circling the laser multiple times to form a reference through hole that pierces the first conductor layer, the insulating layer and the second conductor layer in order; a first machine hole-forming process for irradiating the laser on the workpiece from the first conductor layer side to form a first machine hole that pierces the first conductor layer and reaches the insulating layer; and a second machine hole-forming process for positioning the reference through hole using an image taken from the second conductor layer side and irradiating the laser on the workpiece from the second conductor layer side to form a second machine hole that pierces the second conductor layer and reaches the insulating layer and also communicates with the first machine hole. In the reference through hole-forming process, the various circlings in the multiple circlings of the laser are made to differ from each other so that the amount of heat input into the side surface of the reference through hole in the radial direction from the central axis of the reference through hole is uniform.