Abstract: With the aim of developing an optimal sample pretreatment for the determination of illegal added rosiglitazone in dietary supplement,a method was developed using carbon nanotubes dispersive solid- phase extraction combined with high performance liquid chromatography( HPLC). Key parameters that affect impurity removal and recovery of samples were optimized including the sample extraction solvent and extraction time,the type,composition,amount of purifying agent and sample purifying time. The optimal sample pretreatment conditions were achieved as follows: samples were ultrasonically extracted for 20 min using absolute methanol,and.then cleaned up for 1 min with multi- walled carbon nanotubes( MWCNTs)and N- propyl ethylenediamine( PSA) before analysis. The HPLC method established based on the optimized sample pretreatment conditions exhibited a good linear relationship from 1.0 to 50.0 μg / m L,with the correlation coefficient of 0.9997.The limit of detection and quantification was 0.02 and 0.06 μg / m L,respectively.The mean spike recovery rates for rosiglitazone in dietary supplement were in the range of 77.3% ~93.2%,with relative standard deviations( RSD) less than 10%. This method was simple,rapid,low- cost and applicable for the determination of illegal added drug rosiglitazone in dietary supplement.