Novel fungal endoglucanases with substantial performance at low temperatures are disclosed. The endoglucanases are conveniently produced by recombinant technology, and means for their production are described. The endoglucanases are used for treating cellulosic material, especially in textile industry, e.g. in biofinishing or biostoning. They may also be used in detergents, in animal feed and/or in pulp and paper industry or bioethanol production.