Abstract: In different districts with plenty of LAS, a Phenylobaterium mobile GZ6 which can efficiently degrade linear alkylbenzenesulfonate (LAS) is selected by separating and purifying. It is aerobic gram-negative short-rod (0.5 to 0.8 by 1.0 to 2.0 urn). Optimum growth occurs at 28 ℃ and pH = 7.0. GZ6 is cultivated by the shaking table at 28 ℃ and 170 r/min. Through ultraviolet (UV) spectrum analysis, the authors find that at the 8th hour in the process of the degradation of LAS by GZ6, there occurs the biggest ABS. So through separating the 8th hour's sample by HPLC and further analyzing by MS, they give out the primary mechanism of degradation of LAS by GZ6.