A newly isolated thermophilic fungus, NH-139, identified as Rhizumucor pusillus (Lindt) Schipper produced only a single form of raw-starch-absorbable, raw-starch-digesting glucoamylase on solid wheat bran medium at 45°C. The electrophoretically homogenous preparation of glucoamylase, molecular weight 68,000, had its optimal temperature on gelatinized starch at 65°C and on raw corn starch at 50°C. However, this raw-starch-digesting glucoamylase, unlike other glucoamylases, could not completely hydrolyze glycogen but hydrolyzed it to the extent of 80% as glucose, and is classified as type B. The subtilisin-modified glucoamylase of this strain, molecular weight 60,000, still belonged to type B in the hydrolysis curve on glycogen and lost the ability to digest and adsorb onto raw starch.