Abstract: Methods of GC-MS(SIM) and GC-MS/MS were applied to simultaneous determination of 6 diuretics in tea drinks with microwave assisted derivatization.The sample was extracted with ethyl acetate and purified on Florisil SPE column.Under the microwave-heating condition,the time of derivatization with CH3I,acetone and K2CO3 was shortened to 8 min.It was found that values of intraday and interday RSD′s (n=6) of the method were less than 10%.Values of detection limit (3S/N) and lower limit of determination (10S/N) by GC-MS/MS was far lower than those obtained by GC-MS(SIM).The method of GC-MS/MS was applied to the analysis of samples of tea drinks,giving values of recovery in the range of 65.1%-108.5%.