A nitride-based semiconductor laser device capable of elongating the life thereof is obtained. This nitride-based semiconductor laser device comprises a first cladding layer consisting of a first conductivity type nitride-based semiconductor, an emission layer, formed on the first cladding layer, consisting of a nitride-based semiconductor and a second cladding layer, formed on the emission layer, consisting of a second conductivity type nitride-based semiconductor, while the emission layer includes an active layer emitting light, a light guiding layer for confining light and a carrier blocking layer, arranged between the active layer and the light guiding layer, having a larger band gap than the light guiding layer.