NOVELTY - A light oil composition is obtained by mixing an animal/vegetable fat (derivative) with a sulfur-containing hydrocarbon compound to obtain raw oil, and contacting the raw oil with sulfide catalyst. The composition contains fractions having 95% distillation temperature of 360degreesC or less, sulfur content of 10 mass ppm or less, and oxygen content of 1 mass% or less. The composition has oxygen content of 1 mass% or less, fatty-acid alkylester content of 3.5 mass% or less, methanol content of 0.01 mass% or less, and sulfur content of 10 mass ppm or less.    USE - As fuel for vehicles.    ADVANTAGE - The light-oil composition has excellent durability, ignitability, oxidative stability, and low-temperature flowability, and reduced carbon-dioxide emission. The light-oil composition reduces aldehydes in exhaust gas.    DETAILED DESCRIPTION - A light oil composition is obtained by mixing an animal/vegetable fat and/or ingredient derived from an animal/vegetable fat with a sulfur-containing hydrocarbon compound so as to result in a sulfur content of 1 mass ppm to 2 mass% to obtain raw oil to be treated and bringing the raw oil into contact with a sulfide catalyst in the presence of hydrogen. The sulfide catalyst comprises a porous inorganic oxide containing two or more elements chosen from aluminum, silicon, zirconium, boron, titanium and magnesium, and metal(s) chosen from periodic table group 6A and 8. The contact process is carried out at a hydrogen pressure of 2-13 MPa, a liquid space velocity of 0.1-3 hour-1, a hydrogen oil ratio of 150-1500 NL/L, and reaction temperature of 180-480degreesC. The light-oil composition contains fractions (10-80 vol.%) having 95% distillation temperature of 360degreesC or less, a sulfur content of 10 mass ppm or less, and an oxygen content of 1 mass% or less. The light-oil composition has an oxygen content of 1 mass% or less, a fatty-acid alkylester content of 3.5 mass% or less, an acid value of 0.13 mgKOH/g or less, a methanol content of 0.01 mass% or less, and a glyceride content of 0.01 mass% or less, and a sulfur content of 10 mass ppm or less.