Abstract: Ethylene oxide in air was determined by gas chromatography. The ethylene oxide in air of workshop was sampled by using passive diffusion air monitoring badge as sampler, and converted into stable 2-bromoethanol. A mixture of CH2Cl2-CH3OH(10+90) was used to extract 2-bromoethanol from the sampler and 1.0 μL of the extract was taken for GC analysis. The amount of 2-bromoethanol found was converted into content of ethylene oxide. Linear relationship between values of peak area and mass concentration of ethylene oxide was found in the range of 2.8-33.6 mg·L-1 , with its detection limit (3S/N) of 0.38 mg·L-1. Test for recovery was made by standard addition method, giving results of recovery in the range of 81.8%-92.3% . Values of RSD′s (n=6) found were less than 5%.