Abstract: A new PVC Au (111) ion-selective electrode is reported in this paper, The sensor membrane is composed of diantipyrylmethane (DAM)-Aucl₄^- (10 mg),dibutyl phthalate (DBP) (0.2ml), PVC (170mg). The electrode exhibited Nernstian response in the CAuCl₄^- ranging fnm 6×10^-7 to 1×10^-2M with a slope of 58±1mV/pM (22℃) in the medium 0.5M HC1. The limit of detection is 3.2×10^-7M.The electrode that is used for three months continually remained good speciality. Trace gold in ores are collected and separated by foamed plastics, and are determined by this ion-selective electrode. The satisfactory results are obtained in determination of ores.