α-d-galactosidase (α-d-galactoside galactohydrolase, EC 3.2.1.22) activity in the normal endosperm increased with age continually up to endosperm maturity. In contrast, makapuno α-d-galactosidase was hardly detected in almost all stages of development except the last, where its activity was 8300-fold lower as compared to the normal. The possible role of α-d-galactosidase in the formation of the makapuno endosperm is discussed.