A cbh2 cDNA encoding Trichoderma reesei QM9414 cellobiohydrolase II, located on the expression victor whose copy number is controlled by the level of gentamicin, was successfully expressed under the control of a human cytomegalovirus promoter in the fission yeast, Schizosaccharomyces pombe. The 24-amino-acid leader peptide of the cbh2 gene was recognized by the yeast, enabling the efficient secretion of the heterologous cellobiohydrolase. The transformed S. pombe strain produced over 115 mu g cellobiohydrolase proteins/ml rich medium supplemented with malt extract and 100 mu g/ml gentamicin. The molecular masses of the recombinant cellobiohydrolases. secreted as two molecular species, were estimated to be 70 kDa and 72 kDa by sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS-PAGE). Deglycosylation treatments revealed that the recombinant enzymes were overglycosylated and scarcely susceptible to alpha-mannosidase. The recombinant enzymes showed no carboxymethylcellulase activity, but showed similar characteristics to those of a native enzyme purified from T. reesei in their optimum pH and temperature, pH and temperature stabilities, and V-max values toward phosphoric-acid-swollen cellulose as substrate, except that their K-m values were about four-fold higher than that of the native enzyme.