This standard specifies a method for the determination of lead content in mg and magnesium alloys by flame atomic absorption spectroscopy (AAS), which is applicable in the range of 0.0010% to 0.010%. After the sample is dissolved by muriatic acid, the lead is separated and enriched by co-precipitation with iron hydroxide as the carrier. Absorption of lead measurement at 283.3 nm by air-acetylene flame in muriatic acid medium. This method is suitable for quality control and composition analysis of mg and magnesium alloys, especially in application scenarios where high accuracy is required.