A method for the simultaneous determination of precious metals and matrix elements in Fe and Cu ores is studied. The instrument used is ICAP-9000 polychromator and its accessory monochromator(N+1). Interferences of matrix are eliminated by matrix matching method, i.e. the influence of matrix was corrected by minus equivalent concentration method. The experiments show that the method is simple, sensitive and reliable; especially, suitable for determination of Au in Cu-Au ores.