The results of experimental studies on the development of gas chromatographic method for the determination of 1,3-butadiene and ethylene oxide in ambient air at the level of reference concentration with the use of sorption of the compounds studied from ambient air on the adsorbent TenaxTA in conjunction with optimum conditions of thermal desorption and the use of capillary gas chromatography are presented. The parameters of adsorption, thermal desorption and gas chromatographic determination of 1,3-butadiene and ethylene oxide in ambient air have been justified. A high sensitivity of gas chromatographic determination in the range of concentrations (in mg/m3) of 1,3-butadiene, 0,002 - 5, 0, ethylene oxide 0.005 - 1, 0 with 25% uncertainty in the determination has been reached .