Abstract: This study focused on screening high efficiency cellulose decomposing fungus from humus in campus.The fungus were firstly screened through the ratio of hydrolytic circle and colony diameter which growing in Congo red plate, and then cultured in liquid medium with dry straw powder as carbohydrate supply for filter paper activity ( FPA) .The fungus were identified by microbiology at last.Results showed that the fungus was identified as Cladosporium cladosporioides by colony morphology, microscopic morphology and transformed cells DH5a.The filter paper activity of it was 247.48U /mL.It would be a potential cellulose degrading fungus for research.