Isoamylase (EC 3.2.1.68, debranching enzyme, glycogen α-1,6-glucanohydrolase) is an enzyme with systematic name glycogen 6-α-D-glucanohydrolase. It catalyses the hydrolysis of (1→6)-α-D-glucosidic branch linkages in glycogen, amylopectin and their β-limit dextrins. It also readily hydrolyses amylopectin.