Several glycosidases present in extracts of pancreatic tissue have been found in pancreatic juice. The corresponding enzyme systems in pancreatic juice and pancreatic tissue extract have identical pH optima and similar curves of pH activity. Velocity-substrate relationships of β-glucosaminidase, β-galactosaminidase, α-D-mannosidase, and α-L-fucosidase in pancreatic juice have been estimated.