Abstract: The effects of different organic solvents, ρ(pyrene), φ(organic phase) and agitation rate were studied on pyrene degradation by Ochrobactrum sp. PW in TPPB, to reduce the toxicity of PAHs to microbes and to promote the degradation of PAHs. The results showed that when φ(organic phase) was 10.0% and ρ(pyrene) was 100-1000 mg/L, pyrene degradation rates in pure water, water-silicon oil, water-dodecane, water-undecanol, water-n-decane, water-hexadecane and water-octadecane were 92.5%-13.9%, 69.3%-20.1%, 79.6%-23.3%, 81.9%-26.9%, 86.7%-28.1%, 87.7%-34.1% and 89.6%-27.4%, respectively in eight days. This result showed that pyrene degradation was promoted at high ρ(pyrene) but inhibited at low ρ(pyrene) in TPPB. Among the six organic solvents studied, the highest degradation rate of pyrene was observed in hexadecane. The optimum proportions of φ(octadecane), φ(hexadecane) and φ(undecanol) were 5.0%, 2.5% and 5.0% when ρ(pyrene) was 100 mg/L; all were 20.0% when ρ(pyrene) was 1000 mg/L. This result showed that ρ(pyrene) has an effect on the optimum of φ(organic phase) in TPPB. A larger pyrene degradation rate was shown to result from an increase of the interfacial area and mass transfer rate with the increase of agitation rate. For example, the pyrene degradation rate was 50.1%-75.6% in water-octadecane, and was 54.1%-79.1% in water-hexadecane when the agitation rate was 50-200 r/min. The results indicated that TPPB is a potential way to treat pollution with the high concentration of PAHs effectively, and the optimization of TPPB technique was the result of various factors.