The invention relates to the technical field of biofuel, in particular to wheat straw biomass particles. The wheat straw biomass particles comprise 55-75 parts of wheat straw, 30-45 parts of rice husk, 25-32 parts of corn stalk, 15-18 parts of waterweeds, 22-40 parts of sawdust, 20-35 parts of desulfurized coal slag, 50-60 parts of Chinese herbal medicine dregs, 5-12 parts of gypsum, 0.8-5 parts of swelling agent, 10-30 parts of paraffin wax, and 8-20 parts of squalane powder. A preparation method is also provided and comprises the steps of drying, segmenting, pulverizing, mixing, stirring, press forming, drying, granulating and packaging. According to the invention, the desulfurized coal slag and sawdust are added to the raw materials, so that the burning value of the biomass particles are higher than that of conventional biomass particles; the gypsum is added, and the prepared biomass particles are high in molding rate and not easy to loose due to good consolidation property of the gypsum; and the swelling agent is added, so that the biomass particles are loosened and can be fully burned when burned.