Abstract: One bacterium, which has testosterone degradation efficiently, was isolated from the sludge, Fujian and named C53-20.The results of morphological characteristics and the similarity analysis of the 16 SrDNA sequence suggest that it is a Klebsiella pneumonia.In addition, testosterone degradation activity in 35-40℃and pH6.0-8.0range was assayed, and our results suggest that the optimum activity is at 37℃and pH6.5, respectively.Testosterone can be utilized as sole carbon and energy sources and the degradation rate to cholesterol was 45%, with1mmol·L-1 concentrations within 12 hours.Our results suggest that the strain has potential application prospects in environmental remediation of androgen contaminated areas.