The standard "GB/T 15717-2021 Vacuum metal platings Film thickness test method, resistance method" specifies a detailed method for the measurement of vacuum metal platings Film thickness on insulating soft substrates by resistance method. The standard includes the test principle, device requirements, specimen preparation, test steps, result calculation and reporting format. The method is based on Ohm's law and determines the film thickness of metal platings by measuring their resistance value. It is suitable for platings detection of various insulating soft substrates. The standard ensures the conformity and accuracy of the test and provides reliable technical support for the quality control of metal platings.