The invention relates to the technical field of preparation of car bumpers, in particular to a car bumper capable of acquiring high safety performance and a preparation method of the car bumper. The car bumper is prepared from, by weight, 110-120 parts of polypropylene, 20-30 parts of polyvinylidene fluoride, 10-20 parts of polyacrylonitrile, 20-22 parts of polyolefin elastomers, 3-6 parts of ethyecellulose, 0.6-0.9 part of diethylene glycol, 7-8 parts of iron mine powder, 2-3 parts of silicon carbide, 0.1-0.6 part of heat stabilizer, 13-15 parts of filler, 1.2-1.4 parts of antioxygen, 0.7-0.9 part of bismaleimide and 1-2 parts of lubricant. The car bumper and the preparation method thereof have the advantages that the strength and toughness are high, the energy absorption effect is good, the requirement for driving safety performance can be met, and the requirement for weight reduction of a whole car is met; through the injection molding process, the car bumper has very high impact resistance, and the defects of an injected part are controlled to the maximum degree; a coating is utilized, baking is not needed, the spraying procedure of the car bumper is shortened, and the production efficiency is improved; meanwhile, the car bumper has the effects of resisting water and preventing dampness and corrosion.