A method for manufacturing a nitride semiconductor laser element, equipped with a laminate that has a first conductivity type nitride semiconductor layer, an active layer, and a second conductivity type nitride semiconductor layer on a substrate, and constitutes a resonator, comprises the steps of: forming a first auxiliary groove having an exposed region extending in the resonator direction of the laser element and in which at least the second conductivity type nitride semiconductor layer and the active layer are removed from the second conductivity type nitride semiconductor layer side on both sides in the resonator direction of an element region where the laser element is formed on the surface of the laminate, thereby exposing the first conductivity type nitride semiconductor layer, and two protrusion regions that are narrower than the exposed region and protrude in the resonator direction from the exposed region; forming a second auxiliary groove whose angle of inclination of the side faces with respect to the normal direction versus the substrate surface is greater than that of the first auxiliary groove within the exposed region; and dividing the substrate and the laminate with using the second auxiliary groove.