GB/T 22885-2008 is a test standard for the colour fastness of leather to water. It specifies the method of testing the colour fastness of leather under the action of water, and specifies the parameters of the equipment required for the test, such as constant temperature and humidity devices. The treatment process of leather samples in water is described in detail, including key conditions such as soaking time, water temperature, water quality, and the standard for evaluating colour fastness. The grade is determined by comparing the change of leather color before and after the test with the standard sample card. According to this standard, the fading of leather after encountering water can be accurately judged, which provides an important basis for leather products enterprises to control the mass of products and improve the durability of products.