A first semiconductor laser element is formed on a surface of the first substrate and including a first active layer. A second semiconductor laser element is bonded to the first semiconductor laser element with a first insulating film interposed therebetween. A first electrode is connected to the first semiconductor laser element. A second electrode is arranged on the surface of the first semiconductor laser element with the first insulating film interposed therebetween and connected to the second semiconductor laser element. The first semiconductor laser element has an optical waveguide formed in a region where the second semiconductor laser element is not bonded while the first electrode is arranged on the region, and the second electrode is formed to extend from between the second semiconductor laser element and first insulating film toward the region.