Abstract: A method for determination of vanillin and ethyl vanillin in beverages by gas chromatography( GC) and gas chromatography- mass spectrometry( GC- MS) was established.If samples were colorless,firstly extracted by ether,centrifuged and then the supernatant fluid were purified by 0.22 μm organic phase membrane and quantified by GC and GC- MS. If samples were color,firstly extracted by ether,centrifuged and then the supernatant fluid were collected and enrichment to nearly dry,then dissolved by acetone,purified and concentrated by Carbon-GCB.Finally,they were quantified and certified by GC and GC- MS,using external standard. The recoveries of vanillin and ethyl vanillin by the GC method and GC- MS method ranged from 80% to 105% and from 81% to 110%respectively,as well as RSD was less than 6.0%.GC instrument was operated simply and that the cost of operation was relatively low,so it can be widely used in vanillin and ethyl vanillin daily testing in beverages.GC- MS method using selected ion scan( SIM) to rule out false positives sample which was tested by GC method and made the results more accurate and reliable.The two methods were complement each other,which were suitable for the daily determination and quality control of vanillin and ethyl vanillin contents in beverages.