Abstract:A method for determination of iridium in iridium complex materials by ICP-AES with sodium peroxide alkali fusion decomposition sample, oxidation of sodium chlorate solution , separation of iridium by tellurium -tin(II) chloride coprecipitation was established.The sample decomposition temperature, sodium chlorate oxidation and separation of iridium by tellurium coprecipitation, interference and elimination of coexisting elements, sample spiking recovery rate,the accuracy and precision of method were systemic investigated. Mixing about 0.10 g～0.50 g sample with 5 g sodium peroxide，melting in muffle furnace at 750℃ for 30 min, leaching with water after cooling,acidifying with 30% hydrochloric acid, adding sodium chlorate solution to oxidize low valent iridium to +4, separation iridium by tellurium coprecipitation and determination of iridium content by ICP- AES. Platinum, palladium, rhodium, and ruthenium coexisting in the determination solution has no interference with 224.268 nm iridium spectral lines.Copper interference with 224.268 nm iridium spectral line so 237.277 nm iridium spectral line should be selected to copper containing sample.The method applied to detect samples with 0.5% to 50% iridium content,the recovery rate of sample spiked is 98.4%~ 101.2%，the relative standard deviation(RSD, n=9)is 0.4%~1.4% . Compared with the national standard method, the relative deviation of the analysis results is less 1%.