[en] The decomposition experiment of industrial flue gas contain volatile organic compound, such as dichloromethane (CH₂CI₂) using irradiation technique by electro beam and γ-ray has been carried out. The experiment was done in batch system with 3 different ways of irradiation. In the experiment, the glass reactor were irradiated by electron beam in certain time with different dose rate (1,33 - 10,67 kGy/s). In the second experiment, the glass reactor were irradiated by electron beam in the certain time with a same dose rate (1,33 kGy/s), and in the third experiment, the glass reactor were irradiated by γ-ray from ⁶⁰CO source in certain time with a dose rate of 2kGy/h. the decomposition product of dichloromethane gas were CO, CO₂, CI₂, HCI and COCI₂ (phosgene). Those product could be released to the environment after being dissolved in water, to covert phosgene to HCI and CO₂; while CO and CO₂ were adsorbed by active carbon. The result of the first experiment has shown that decomposition of dichloromethane was 65 % at the doses of 16-32 kGy. In the second and the third experiment, the decomposition of dichloromethane were 100% respectively at a dose of 32 kGy. It was found that at small dose rate dichloromethane can be easily decomposed, because the probability of active species react with dichloromethane on small dose rate are higher than or large dose rate. Key words : dichloromethane (CH₂CI₂), electron beam, xγ-ray, phosgene (COCI₂)