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Polyurethane elastomers are polymer materials that possess the properties of both plastics and rubbers, offering excellent mechanical properties such as a wide range of hardness levels, high strength, high elongation, and good tear strength. However, during use, polyurethane elastomers develop cracks due to mechanical damage or certain internal factors, which leads to tearing and failure; this is one of the most common types of failure in such products. For many polyurethane products, such as rubber rollers, rubber hoses, and solid tires, the quality of their tear resistance is directly related to their service life. Therefore, the tear test of polyurethane elastomers is an important physical property test. Rubber tearing starts at the defects or microcracks present in the rubber, and then gradually progresses to fracture. Tear strength refers to the energy required to create a unit of crack in a specimen of a given thickness; it is a failure phenomenon resulting from the rapid expansion and cracking of cracks or fissures in the material when subjected to stress. The so-called tear resistance is the ability of a material to resist tearing forces. The tear strength of polyurethane elastomers is generally tested using rubber tear strength standards. The tear resistance of polyurethane elastomers is greatly influenced by factors such as the chemical structure of the material, the physical structure of the stress, stress distribution, strain rate, and sample size. The text briefly discusses the effects of chemical structure and external factors on the tear strength of polyurethane elastomers. The types, shapes of specimens used for measuring tear strength, as well as the relevant standards: There are currently many methods for testing rubber tear strength, and the specimens used fall into two categories – those without cuts and those with cuts ； The shapes of the specimens used also vary; the three most common shapes are pant shape, right-angled shape, and crescent shape. Correspondingly, there are pant shape tear strength, right-angled tear strength without a cut, right-angled tear strength with a cut, and crescent shape tear strength with a cut. The standards for rubber tear strength include **GB/T standards in China, ASTM standards in the United States, ISO standards internationally, and DIN ISO standards in Europe; the international standards and European standards are largely similar to each other. Table 1 shows the standard numbers, specimen types, and shapes for testing rubber tear strength. The tear strength value is related to the specimen shape, stretching speed, and testing temperature. Different sample shapes generally have a significant impact on the test results of tear strength. For the rectangular shape, the tear strength with a notch is lower than that without a notch. The right-angled tear is used to determine the mixed strength of initial tearing and tear propagation. The stretching speed of the testing machine, that is, the tearing speed, has a certain influence on the tearing behavior of rubber. During high-speed tearing, the tearing exhibits a brittle failure akin to that of a rigid body ； While under slow tearing, elastic failure is observed. It is generally believed that as the stretching speed increases, the tear strength decreases. This may be due to the increased stretching speed, which causes stress to concentrate more easily at the tear point, thereby reducing the resistance to tearing.