A semiconductor laser device includes an n-type semiconductor substrate, an n-type cladding layer laminated on the semiconductor substrate, an n-side light guiding layer laminated on the n-type cladding layer, an active layer laminated on the n-side light guiding layer, a p-side light guiding layer laminated on the active layer, and a p-type cladding layer laminated on the p-side light guiding layer. The sum of the thicknesses of the n-side and p-side light guiding layers is such that the first and higher order modes of oscillation can occur in the crystal growth direction. A low refractive index layer having a lower refractive index than the n-type cladding layer is located between the n-side light guiding layer and the n-type cladding layer, and the active layer is displaced from the lateral center plane of the light guiding layer structure toward the p-type cladding layer.