In-situ analysis and mapping of sulfide minerals for trace elements and sulfur isotopes using LA-(MC)-ICP-MS have important application in resolving a variety of geological problems [1,2,3].However,constraints on quantitative trace element analysis and mapping of sulfides(such as pyrite)are still not well understood at the present,and no report is available for sulfur isotope mapping although in-situ spot sulfur isotope analysis has been carried out in a few laboratories.In this study,we developed LA-ICP-MS and LA-MC-ICP-MS methods to mapping both the trace elements and sulfur isotopes on sulfides(mainly pyrite).We applied spot analysis of sulfur isotopes to evaluate the matrix effects that may involve in mapping analysis.The samples we used contain a complex mineral assemblage of pyrite with magnetite and siderite in the matrix,and our experiment demonstrates that no matrix effect from magnetite and siderite occurs on S-isotope mapping analysis of pyrite.Both Fe and S were previously used as internal standard elements to normalize the trace element concentrations during LA-ICP-MS analysis of pyrite.Our experiment shows that Fe is the better choice because the normalized CPS ratio of trace elements with Fe is much more stable than using S as internal standard.The samples we examined in this study come from the Chengmenshan Cu deposit in Jiangxi Province,and three generations of pyrite are found in this sample,namely(1)early stage pyrite(Py-e)in association with siderite and magnetite,the pyrite was likely transformed from marcasite;(2)main ore stage pyrite(Py-a)associated with chalcopyrite-sphalerite-bornite;(3)late stage vein of pyrite(Py-l).The S-isotope mapping shows that the Py-l has significantly higher δ34S than the Py-e and Py-a.The trace element mapping also demonstrated significant differences between Py-l,Py-e and Py-a.These in-situ analyses of trace elements and sulfur isotopes of different generation of pyrite may provide a powerful tool for understanding ore-forming processes.