Abstract: A method for the determination of bromine and iodine in plant and biological sample by ICP-MS was proposed with laser ablation solid sample introduction technique.Disc sample was prepared from powder sample by press-moulding.Influential factors,including parameters of laser ablation system,flow rate of carrier gas,resolution ratio of the ICP-MS instrument,and choice of internal standards were studied and optimized.Detection limits (3s) of the method found were 0.12 μg·g-1 for Br and 0.08 μg·g-1 for I.The proposed method was applied to the determination of Br and I in 6 CRM′s,giving results in consistency with the certified values.