Cellulosic biomass is one of the most dominant waste materials from various industries. Cellulose degradation and its utilization is important for global carbon sources. The value of cellulose as renewable source of energy has made its hydrolysis a subject of research and industrial interest. The present investigation is based on isolation, screening, and characterization of cellulolytic bacteria and determination of their cellulolytic potential. The work also concentrates on production of cellulase enzyme by submerged fermentation and its partial purification by centrifugation. Enzyme activities of selected isolates were determined by DNS method and finally application of potential isolates in degradation of various natural cellulosic substrates was carried out.