Abstract: It was found that platinum(Ⅳ) was quantitatively extracted into ethanol in the form of Pt(SCN)2-6 in the presence of relatively large amount of ammonium sulfate from a solution of pH 3.0.The optimum amounts of the reagent present in the extraction system were as follows: NH4SCN 20 g·L-1,(NH4)2SO4 300 g·L-1 ethanol 0.30 mL·mL-1.Under these conditions,Pt(Ⅳ) was effectively separated from appropriate amounts of Ni(Ⅱ),Cr(Ⅲ),Co(Ⅱ),Fe(Ⅱ),Mn(Ⅱ),Al(Ⅲ) and Rh(Ⅲ).This method has been applied to the analysis of Ni-Pt/Al2O3 catalyst as a separation process,and 5 determinations of Pt(Ⅳ) in a catalyst sample were performed giving an average result of w(Pt) 0.104% with RSD of 1.7%.