A sugar production method comprising: fermenting a sucrose- and invert sugar-containing juice derived from a plant by using a microorganism in the presence of a sucrase inhibitor, wherein the sucrase inhibitor is selected from the group consisting of silver ion, copper ion, mercury ion, lead ion, methyl-a-D-glucopyranoside, p-chloromercuribenzoate and glucosyl-D-psicose and producing sugar from the fermented juice.
