This invention relates to thermal plastic elastomer (TPE) alloy materials used to manufacture mobile airbag cover, which is characterized by using SEBS I and SEBS II, polyolefin elastomer (POE), polypropylene (PP) rubber filling oil, high and low temperature modifier, antioxidants and other additives as the raw materials. The preparation method includes: mixing SEBS I, SEBS II, and rubber filling oil with a high-speed machine at low-speed to obtain the oil-filled SEBS, adding POE I, POE II, polypropylene, antioxidants, and other additives in the high-speed machine and mixing at high speed, adding oil-filled SEBS and mixing at high-speed, extruding, and granulating. The advantages of this invention are as follows: brittle transition temperature is below minus 40degreeC, materials are not softening at 80degreeC, the material has good heat-resistance (100degreeC, seven days aging experiments, properties dropped < 50%) and high-outdoor (UV) properties, and the material can be processed easily and color directly without paint.