Abstract: A laser processing method includes a first step of irradiating a surface of a composite material with a laser to form a hole processing groove on the composite material by scanning first paths from an outside corresponding to an inner peripheral surface side of a through hole to be formed to an inside corresponding to a center side of the through hole to be formed, the first paths extending across a width direction of the hole processing groove; and a second step of irradiating and penetrating through the hole processing groove with the laser to form the through hole by scanning second paths from the outside to the inside after the first step, the second paths extending across the width direction of the hole processing groove. The laser used at the first step has a smaller heat input amount per unit time than the laser used at the second step.

Abstract: A laser processing method includes a first step of irradiating a surface of a composite material with laser to form a hole processing groove on the composite material in a manner of scanning paths from an outside corresponding to an inner peripheral surface side of the through hole to be formed to an inside corresponding to a center side of the through hole, the paths being across a width direction of the hole processing groove; and a second step of irradiating and penetrating through the hole processing groove with the laser to form the through hole in a manner of scanning paths from the outside to the inside after the first step, the paths being across the width direction of the hole processing groove. The laser used at the first step has a smaller heat input amount per unit time than the laser used at the second step.