The ASTM D5150-92 (2017) standard test method is used to evaluate the hiding power of architectural coatings through the roller Spreader in practical applications. Unlike the hiding power test in the laboratory using a scraper coating applicator, this method simulates the Spreader effect under actual use conditions. Due to the rheological characteristics of the Coating and the interaction of the coating applicator, the hiding power in practical applications is often lower than the laboratory test results. This method aims to provide the actual hiding performance index of the Coating under the application conditions of experienced workers, providing users with a more accurate basis for evaluating the Coating performance.