In order to solve the problem of "three sludges" in the treatment of oily wastewater from oil refinery, a strain GJ was isolated from the oily sludge of Daqing Oilfield, which can produced surfactant and degraded petroleum hydrocarbon. Through morphological observation, physiological and biochemical experiments and 16S rDNA sequence analysis, the strain GJ was identified as Shewanella sp.. The strain GJ was applied to the degradation experiment of scum and biochemical sludge, and the degradation kinetics of scum and biochemical sludge by GJ was discussed. After extraction and purification, TLC and FTIR analysis, it was confirmed that GJ product was a glycolipid surfactant. In the experiment of scum and biochemical sludge degradation, the degradation rate of petroleum hydrocarbon reached the highest, which was 81.11% and 83.21% respectively at the 7th day of strain GJ. Logistic growth model, Luedeking-Piret model and first-order reaction kinetics model can well simulate the growth of GJ cell, the synthesis of surface active products and the degradation of petroleum hydrocarbons. It is preliminarily inferred that GJ bacteria take petroleum hydrocarbon as carbon source, and secrete surfactant at the oil-water interface during the growth process, increase the contact degree between the strain and petroleum hydrocarbon, and promote the uptake and metabolism of petroleum hydrocarbon by GJ bacteria and self proliferation of GJ bacteria.