Abstract: Palladium chloride and ascorbic acid were used as mixed matrix modifier in the GF-AAS determination of lead in urine,in order to raise the ashing temperature to 1 000 ℃ and also to lower interferences of those complex co-existing components to a considerable extent.Detection limit of the method was 0.20 μg·L-1.In analyzing urine samples collected from healthy persons,values of RSD′s (n=6) and recovery obtained were in the ranges of 2.54%-4.86% and 92.6%-112.6% respectively.