Abstract:Soil is decomposed by sodium carbonate and zinc oxide,extracted by water. Rh as the internal standard,bromide and iodide are determined by ICP-MS after adsorbed on cation exchange resin. Under optimal working conditions,when the range of bromide and iodide is 0~5.0 μg•g-1,the correlation coefficient of the working curve are 0.999 1 and 0.999 8,the detection limits for bromide and iodide are 0.166 μg•g-1 and 0.051 μg•g-1. The accuracy and precision of this method have been verified by a series soil CRM,the RSD of bromide and iodide are 2.83%~9.45% and 2.14%~9.87%. The pretreatment of this method is efficient and convenient,meanwhile,the detection limits,accuracy and precision are up to the standard,this method is suitable for the detection of large quantities of geochemical sample.