A gallium nitride-based semiconductor laser device with reduced threshold current. The gallium nitride-based semiconductor laser device is provided with an n-type cladding layer, an n-side light guide layer, an active layer, a p-side light guide layer, and a p-type cladding layer. The n-side light guide layer and the p-side light guide layer both contain indium. Each of indium compositions of the n-side light guide layer and the p-side light guide layer is not less than 2% and not more than 6%. A film thickness of the n-type cladding layer is in the range of not less than 65% and not more than 85% of a total of the film thickness of the n-type cladding layer and a film thickness of the p-type cladding layer.