The crop stubbles left out in the field after harvesting (rice and sorghum) and tree residues were routinely burned around the globe which creates serious pollution and health issues [8]. However, all these crop residues represent a biofuel feedstock for ethanol production due to their cheaper cost, easy availability, easy processability, non-hazardous, non-abrasive, recyclable and environmental friendly nature. The aim of the present study is to evaluate the enzymatic saccharification of steam pretreated cellulosic plant biomass by the newly isolated halotolerant marine actinomycetes bacterium, Isoptericola sp. JS-C42 and simultaneous conversion into ethanol by fermentation assisted by Saccharomyces cerevisiae.