Ten strains which can degrade the waste lubricants were isolated from sewage samples of the outfall of a castor oil extraction plant in Inner Mongolia, China, and T-9 strain showed the strongest lubricant degradation ability. The optimal degradation condition of T-9 strain was pH 5.0, and temperature 30℃. T-9 strain could grow well in the medium containing 1%~5% NaCl. T-9 strain was identified as Pseudomonas by the colony morphology, physiological and biochemical characteristics. By improved CEC-L-33-A-93 method, the degradation rate of castor oil-based waste lubricants was 72% when incubated for 7 days under the conditions as following: 10g/L oil, initial pH 5.0, rotation speed of 180r/min, and 30℃. By GC/MS analysis of degradation products, degradation rate was 80%, indicating that the T-9 strain had good castor-based oil degradation ability.