GB/T 6730.55-2019 for the determination of tin content in iron ore. It uses flame atomic absorption spectroscopy (AAS) method, which is suitable for natural iron ore, iron concentrate, sinter and pellet. The standard specifies the determination principle, required reagents and instruments in detail, and standardizes the operation procedures such as sample preparation and analysis steps. The determination range (mass fraction) is 0.002% -0.20%. The standard provides a unified method for the accurate determination of tin content in iron ore, which is of great significance for controlling iron ore mass and guiding related production and application.