The invention relates to the technical field of thermoplastic engineering plastics, particularly to an alloy antistatic material for wafer trays, and a preparation method thereof, wherein the alloy antistatic material comprises, by weight, 30-50 parts of polyphenylene ether, 10-40 parts of high-impact-resistant polystyrene, 8-12 parts of electric-conduction carbon black, 3-6 parts of a styrene butadiene styrene block copolymer, 0.3-0.5 part of a silane coupling agent, 1-3 parts of a styrene-maleic anhydride copolymer, 8-12 parts of electric-conduction carbon black, 0.4-1 part of a lubricant, 3-4 parts of triphenyl phosphate, and 0.3-0.6 part of an antioxidant. According to the present invention, the alloy antistatic material has good mechanical property, and additionally achieves the permanent antistatic property of the PPO / HIPS alloy, such that the alloy antistatic material is safe in the packaging, testing and transportation of wafers.