An analytical method was established for the determination of thiacloprid,spirotetramat and its four metabolites residues in litchi and longan by high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS) with QuEChERS cleanup.The residues in samples were extracted with acetonitrile,dehydrated with anhydrous magnesium sulfate and sodium chloride,then purified with C18 and GCB.The extract was separated on a Poroshell-120 EC-C18 column with 0.1% formic acid-acetonitrile as mobile phase by isocratic elution,detected by HPLC-MS/MS with positive electrospray ion source in multi reaction monitoring(MRM) mode,and quantified by external standard method.Results showed that there existed good linearities for six analytes in the range of 1-500 μg/L with their correlation coefficients(r2) more than 0.990.The limits of detection(LODs) and limits of quantitation(LOQs) were 0.03-0.3 μg/kg and 0.1-1.5 μg/kg,respectively.The average recoveries for the analytes at spiked levels of 1,10,100 μg/kg were in the range of 80.4%-99.5% with relative standard deviations of 1.4%-6.4%.The developed method was simple,sensitive,accurate and reliable,and could meet the requirements for rapid screening and monitoring of thiacloprid，spirotetramat and its metabolites in fruits such as litchi and longan.