Two constitutive (1 -+ 4)-P-D-glucosidases from Aspergillu roseus were highly purified (275 and 1059-fold) on DE!AE-Sepharose and hydroxyapatite columns. Electrophoresis on poIy(acIylamide) gels showed for each enzyme, a single protein band containing an enzymic activity that hydrolyses 4-nitrophenyl P-o-glucopyranoside and cellulose. Classical cellulose hydrolysis was obtained by the combined action of three proteins, an endocellulase, an exocellulase, and a P-D-glucosidase. In the case of A. roseus, the purified @-D-glucosidases are able to hydrolyze the cellulose substrate giving D-glucose as the only end product. Physi~o-chemical features of these glycosylated enzymes such as optimum pH, molecular weight, K,, and substrate specificity were determined. SOMMAIRE Deux (1 --, 4)-fi-D-glucosidases (p-o-glucoside glucohydrolase, EC 3.2.1.21) constitutives d'Aspergillw roseus ont CtC hautement purifiCes (275 et 1059 fois) sur des colonnes de DEAE-Sepharose et d'hydroxyapatite. L'tflectrophor&se sur gel de poly(acrylamide) montre pour chaque enzyme, une seule bande protCique capable ~hydro~yser aussi bien le 4-nitroph~nyl-~-D-glu~p~anoside que la cellulose. L'hydrolyse de la cellulose est classiquement obtenue par Faction combinie de trois protbines: une endocellulase, une exocellulase et une P-D-glucosidase. Dans le cas d'A. ruseus, les @-D-glucosidases purifiies hydrolysent le substrat cellulose et lib&rent du o-glucose comme unique prod& de la r&action. Les caractiristiques physico-chimiques de ces enzymes glycosylies, tels que pH optimum, poids mol&culaire. K, et sp&ificit& de substrat sent dtterminies.