Abstract: A method of AFS was used for the determination of arsenic and mercury in soil.The sample was treated by microwave digestion,and the interfering ions were removed by using the On-Guard H pretreatment column.Under optimized conditions,the linearity range of arsenic and mercury was 0.50-8.00 μg·L-1,with detection limits (3s/k) of 0.005,0.002 μg·g-1,respectively.The method was applied for analysis of standard substance,giving results in agreement with the certified values and RSD (n=6) less than 4%.