A semiconductor laser diode element includes a semiconductor laser diode portion including a ridge portion extending in a first direction in which a cavity extends, a groove formed along the ridge portion and a support portion formed along the groove on a side farther from the ridge portion and holding the groove between the support portion and the ridge portion and a support substrate bonded to the semiconductor laser diode portion through a fusion layer, wherein the fusion layer is formed so as to be embedded in the groove, a space from the ridge portion to the support substrate and a space from the support portion to the support substrate.