In enzymology, a xyloglucan-specific exo-beta-1,4-glucanase () is an enzyme that catalyzes the chemical reaction
Thus, the two substrates of this enzyme are xyloglucan and H<sub>2</sub>O, and its products are xyloglucan oligosaccharides (exohydrolysis of 1,4-beta-D-glucosidic linkages in xyloglucan).
This enzyme belongs to the family of hydrolases, specifically those glycosidases that hydrolyse O- and S-glycosyl compounds. The systematic name of this enzyme class is [(1->6)-alpha-D-xylo]-(1->4)-beta-D-glucan exo-glucohydrolase. This enzyme is also called Cel74A.