Abstract: To prepare sample solution, 0.500 0 g of the electronic cigarette liquid was taken and mixed with 5 mL of ethanol, in which content of megastigmatrienone (MSTN) was determined by GC. Values of retention times of 5 isomers of MSTN was determined by GC-MS, as basis for identification of MSTN in unknown samples. Quantification of MSTN was performed by comaring the values of chromatographic peak areas of the sample solution with that of the standard sample solution and calculating with the given formula. Same type of the non-polar chromatographic column of HP-INNOWAX capillary column was used both in GC and GC-MS analysis. Test for recovery was made by addition of standard solution of MSTN at 5 concentration levles to a blank cigarette liquid sample as matrixes, values of recovery found were in the range from 91.3% to 92.4%, with RSD′s (n=5) ranged from 0.70% to 0.94%.