Abstract: Establish a method for the determination of total Aspergillus flavus B and G groups in cereals by two-dimensional liquid chromatography with a simulated post column derivatization system.Uses 68%water,16%acetonitrile,and 16%methanol as mobile phases,with equal elution and a flow rate of 1.0 mL/min;Column temperature:40℃;injection volume:100 μL;Derivative solution:5mg/L tribromopyridine(TECH)aqueous solution;Derivative liquid flow rate:0.3mL/min;Derivative reactor temperature:70℃;The fluorescence detector parameter is set to EM=360nm,EX=440 nanometers.The total content of Aspergillus flavus had a good linear relationship,and the linear correlation coefficient r2 was greater than 0.999.Detection limit between 0.01～0.03 μg/kg.The recovery rate of spiking is 87%-103%.Comparing the established method with LS/T 6128-2017 in terms of time,sample processing,and final results,this method is simple,fast,accurate,and highly sensitive.