To provide a method for producing a low sulfur light oil, by which the low sulfur light oil having a high quality can efficiently be produced.

In this light oil-desulfurizing system for producing a low sulfur light oil, a light oil LGO as raw material is separated into a light distillate LLGO and a heavy distillate HLGO in a fractionator 10. The separated light distillate LLGO is hydrogenated in a first hydrogenation device 20 equipped with a hydrogenation catalyst 20B, and heavy distillate HLGO is also hydrogenated in a second hydrogenation device 30 equipped with hydrogenation catalyst 30B and 30D and a zeolite-based catalyst 30C, and is then mixed with the hydrogenated light distillate LLGO in a mixing device 40 to produce a desulfurized light oil DGO. Slightly desulfurized components contained in the light oil LGO as raw material are contained in the heavy distillate HLGO, and then acceleratedly isomerized, when the heavy distillate HLGO is selectively hydrogenated in the presence of the zeolite-based catalyst. Thereby, the desulfurized light oil DGO having a high quality can efficiently be produced.