As the topic says "ISOLATION, PRODUCTION, PURIFICATION, ASSAY& CHARACTERIZATION OF RECOMBINANT CHOLESTEROL OXIDASE FROM NATIVE Brevibacterium sp." The objective of this study is to isolate extracellular cholesterol oxidase (CHO) producing microorganisms to obtain an abundant source of cholesterol oxidase (CHO) for industrial and medicinal needs. Cholesterol oxidase (CHO) is an enzyme, which catalyzes the oxidation of cholesterol and converts 5-cholesten-3-ol into 4- cholesten-3-one. Cholesterol oxidase producing bacteria were isolated from waste of regional oil mill, soil and compost. Twenty-five isolates are tested for cholesterol oxidase activity by screening method. As the result of the screening, CHO producer strain was isolated and identified.Screening and isolation of bacterial strains producing extracellular form of cholesterol oxidase are very important due to its wide spectrum applications. Cholesterol oxidase enzyme has many applications in medicine, agriculture, industry and pharmaceutical sectors.