Abstract: A new method for the separation and determination of dinitrobenzene and chloronitrobenzene isomers is presented. Several typical gas chromato-graphic stationary phases such as OV -101, OV- 25, OV- 210, OV- 225, XE -60,Versamide-930, PEG-20M, Igepal CO-880, DEGA, and EGS ect. were investigated for DNB and CINB isomer separation. The relative retention of these isomers were determinated on packed columns coated with the above stationary phases." Results showed that 0V-225 was an excellent liquid phase for this purpose. Shorter glass capillary column coated with 0V-225 were used for the analysis of the abovement ioned isomers. A 9.2M or 5.8M capillary column is suitable for rapid separation and determination of DNB and CINB isomers.