This standard specifies the determination method of cadmium content in antimony and antimony trioxide, which is applicable to the determination range of cadmium content from 0.0001% to 0.0100%. The sample is dissolved with aqua regia or hydrobromic acid, the antimony is volatilized with muriatic acid-hydrobromic acid to remove, and the residue is dissolved with muriatic acid. Absorbance of cadmium is determined at a wavelength of 228.8 nm by Flame Atomic Absorption Spectrometer (FAAS). This standard details the preparation of the reagent, the conditions of use of the instrument and the determination steps, and provides normative guidance for the accurate detection of cadmium content in antimony and antimony trioxide.