The standard test method for evaluating the relative hiding power of coatings by visual comparison is specified in ASTM D344-2011 Standard Test Method for Assessing the Relative Hiding Power of Coatings by Wiping Test Externals. This method uses a comparative baseplate and a wiping test to test the coating's ability to cover the substrate, and to compare the covering effect of different coatings or coatings. The method is simple and easy to implement, suitable for Coating performance evaluation under laboratory and field conditions, and is widely used in Coating research and development, quality control and application verification. This standard can help producers and users determine whether the hiding power performance of coatings meets expectations, providing a technical basis for product selection and optimization.