Abstract:Abstract: [Objective] The aim of this study was to screen straw-cellulose degrading microorganisms and to investigate their degradation ability of straw-cellulose. [Methods] The methods used to screen the high effect straw-cellulose degrading microorganism included the traditional isolation methods of straw-cellulose degrading microorganism such as holes observation method on filter paper sheet, disintegration test of filter paper scrip, hydrolysis spot diameter measurement method of CMC-Na, weight lose assay method of straw, measurement method of cellulose decomposition rate, measurement method of extracellular enzyme activity. [Results] We isolated 3 fungi with cellulose degrading ability, of which 98MJ was identified as Penicillium oxalicum, W3 as Trichoderma sp., and W4 as Penicillium expansum. Strain W4 possessed high straw-cellulose degrading ability with straw-cellulose degrading rate of 56.3%, cellulose 59.06%,, hemicellulose 78.75% and lignin 33.79% in 10 days. [Conclusion] Strain W4 was a cellulase-producing strain with broad development potential.