This standard specifies a method for the determination of indium content in gold alloys. It is suitable for AuNiln alloys. The determination range is 7% to 10%. In the method, the sample is dissolved with a mixed acid of muriatic acid and nitric acid, and the gold is separated by sulfite reduction. Nickel is separated by dimethyl glyoxaldoxime ethanol solution settling, and then excess disodium ethylenediaminetetraacetate (EDTA) solution is added to complex with indium. Back titration is performed using lead standard titration solution with xylenol orange as indicator to determine the indium content. Reagents and materials need to comply with the relevant provisions of YS/T 371 standard.