Abstract: Three laboratory experiments were carried out to study the biodegradation of Oxyfluorfen herbicide (Goal) in a soil with no history of pesticides application at two temperatures (28 and 40°C) with or without the addition of mineral fertilizers (NPK). Different concentrations of Oxyfluorfen were applied to the soil samples and the herbicide residue was determined using Gas Liquid Chromatography (GLC) at 0 time and then at 15 days intervals for 45 days. Various genera of microorganisms were isolated on different semi-selective media from soils treated with different concentrations of Oxyfluorfen. The ability of these isolates to utilize Oxyfluorfen as a sole source of carbon and energy was studied. Results indicated that biodegradation of Oxyfluorfen in soil incubated at 40°C after 45 days of incubation was better (55.2-78.3%) than in soil incubated at 28°C (17.5-36.6%). Addition of mineral fertilizers (NPK) increased the biodegradation of Oxyfluorfen in soils. Intensive degradation (27.8-55.5%) was observed in NPK fertilized soils incubated at 40°C after 15 days of incubation at all Oxyfluorfen concentrations. Ten potential Oxyfluorfen degraders were identified. Results obtained showed that within 21 days, Bacillus spp. had the ability to degrade 80-95.6% of Oxyfluorfen followed by Pseudomonas sp. (82.2%), Arthrobacter spp. (82.2%), Aspergillus sp. (77.8%), Mycobacterium sp. (75.6%), Micrococcus sp. (73.3%) and Streptomyces sp. (68.9%). It could be concluded that biodegradation of Oxyfluorfen in soils is significantly affected by temperature and the microbial species. These microorganisms are considered as potential candidates for use in any program aiming at decontamination of Oxyfluorfen polluted sites.