The invention relates to a rare earth sulfide and / or rare earth sulfur oxide colorant and a preparation method thereof. A rare earth compound, sulfur, an alkali metal compound, solid carbon and an auxiliary agent are used as raw materials, an initial product of the rare earth sulfide and / or rare earth sulfur oxide colorant is obtained by roasting, water is added to the initial product, then an alkaline compound is added to adjust pH, a treated colorant solid is obtained, an alcohol-water mixed solution is added to the treated colorant solid, then ammonia, PVP, a zinc compound, ethyl orthosilicate and sodium silicate are added for treatment, and washing and drying are carried out to obtain the rare earth sulfide and / or rare earth sulfur oxide colorant. The preparation method has mild reaction conditions, simple operation, low cost, and high production efficiency. The rare earth sulfide and / or rare earth sulfur oxide colorant prepared by the method has stable product performance, high saturation, stable chromaticity, and good particle size uniformity.