PROBLEM TO BE SOLVED: To provide a method for manufacturing sugar solution which is capable of realizing increase in yield of a fermentation product when the solution is used as a fermentation raw material.SOLUTION: There is provided a method for manufacturing sugar solution by using polysaccharide-based biomass as a raw material. The method includes: (I) a step of preparing first solution containing at least oligosaccharide which is obtained by decomposing the polysaccharide-based biomass; (II) a step of allowing the first solution to pass through a first separation membrane and recovering second solution from a non-passing side; (III) a step of performing saccharification treatment in which oligosaccharide is decomposed into monosaccharide to the second solution to obtain third solution; and (IV) a step of allowing the third solution to pass through the second separation membrane, and recovering fourth solution from a passing side to obtain sugar solution. The first separation membrane has an NaCl-rejection
