Organic solvent-tolerant lipases have shown new potential application in biotechnological fields. A novel strain which produced an organic solvent-tolerant lipase was isolated from soils in different areas of China. Based on the morphological, physiological and biochemical features and 16S rDNA sequence of the strain, it was identified as Pseudomonas aeruginosa CS-2. The crude lipase had an improved stability in the presence of acetonitrile and it exhibited stability in presence of benzene, chloroform, n-Hexane, petroleum ether and isooctane. The optimized composition of culture medium was as follows: olive oil 1%, peptone 4%, K2HPO4 0.5%, MgSO4·7H2O 0.1%, gum arabic 0.04%. The optimum condition for lipase production was on the following: temperature 37°C, initial pH 7.5, rotary shaking speed 200 rev/min, culture time 48 h.