This standard specifies methods for the determination of solar reflectance for Paints and varnishes, which are mainly used to evaluate the reflection performance of coatings under sunlight. The standard provides data on the reflection capacity of coatings to solar radiation by measuring the reflectance of coatings in a specific Light spectrum range. This indicator is particularly important for applications such as architectural coatings, roof coatings, to help improve energy efficiency, reduce indoor temperatures, and mitigate the urban heat island effect. The standard describes in detail the test equipment, test conditions, sample preparation and data calculation methods to ensure the conformity of the determination process and the accuracy of the results. This standard is applicable to coatings manufacturers, the construction industry and the environment research field, especially for the development of low energy consumption, Environmental Coatings products is of great significance.