Abstract:The graphite furnace atomic absorption spectrophotometry（GFAAS）coupled with the microemulsion injection method was established to determine the chromium in the edible oil.The formation conditions of microemulsion and the effects of matrix modifier on the results of determination were studied.The heating program of GFAAS was optimized.The results showed that the stable microemulsion can be formulated with 15%edible oil，6%aqueous phase，20%Triton X-100 and 59%n-butanol.The matrix modifier was useless in the microemulsion system，the optimal detection condition of GFAAS with the pre-ashing temperature of 800℃，ashing temperature of 1 400℃and atomization temperature of 2 300℃，respectively.Under the optimal conditions，the relative standard deviation of the test was less than 5%，the detection limit was 0.211 ng/mL，the recoveries were between 90%and 110%，and the results were similar to those of the microwave digestion method treated sample.The method is simple，accurate，practical and suitable for the mass inspection of edible oil samples.