In enzymology, an inulosucrase () is an enzyme that catalyzes the chemical reaction
Thus, the two substrates of this enzyme are sucrose and (2,1-beta-D-fructosyl)<sub>n</sub>, whereas its two products are glucose and (2,1-beta-D-fructosyl)<sub>n+1</sub>.
This enzyme belongs to the family of glycosyltransferases, specifically the hexosyltransferases. The systematic name of this enzyme class is sucrose:2,1-beta-D-fructan 1-beta-D-fructosyltransferase. This enzyme is also called sucrose 1-fructosyltransferase.