A double heterojunction structure type semiconductor laser device comprising an active layer of GaAlAs in which the laser is excited, n-Ga.sub.0.45 Al.sub.0.55 As clad layer and a p-Ga.sub.0.45 Al.sub.0.55 As clad layer sandwiching the active layer between them in order to confine the laser light in the active layer, an n-GaAs current blocking layer disposed between the active layer and the p-Ga.sub.0.45 Al.sub.0.55 As clad layer in order to confine current, and a p-Ga.sub.0.63 Al.sub.0.37 As optical waveguide layer disposed between the active layer and the current confinement layer. The refractive index of the optical waveguide layer is greater than that of the both of the clad layers.