Abstract:Longmala deposit is located in the eastern part of the north Gangdese Pb-Zn-Ag-Cu-Fe belt. Analysis of the S and Pb isotopic compositions of ore minerals in the Longmala deposit indicates that the sulfur isotopic compositions of metal sulfides in the deposit are relatively concentrate, with their δ34S values ranging from 1.6‰ to 3.6‰, showing the characteristics of mantle sulfur. The 206Pb/204Pb ,207Pb/204Pb and 208Pb/204Pb ratios for ore minerals from the deposit are in the ranges of 18.6488～18.6572, 15.7112～15.7166, and 39.1599～39.1763 respectively. The Pb isotopes compositions change in a smaller range, implying that the Pb isotopes have the same origin. The date points of the Pb isotopes are mostly close to the upper crustal Pb evolution curve in the plumbotectonic model. The S and Pb isotope data of the Longmala Pb-Zn-Fe-Cu deposit indicate that the ore materials were mainly derived form the upper crust and there might be the participation of the mantle source.