PROBLEM TO BE SOLVED: To provide an apparatus for manufacturing water for dialysis fluid preparation capable of keeping the concentration of dissolved hydrogen in reverse osmosis water at a high level.SOLUTION: An apparatus 1 for manufacturing water for dialysis fluid preparation includes: a tank 6 for storing water； an electrolytic water generator 7 connected to the tank 6, which is a hydrogen dissolution device for dissolving hydrogen in the water introduced from the tank 6； a reverse osmosis membrane processor 9 connected to the electrolytic water generator 7 for subjecting the water in which hydrogen is dissolved to reverse osmosis membrane treatment； and a circulation passage 27 for circulating reverse osmosis water 25 treated by the reverse osmosis membrane processor 9 and introducing it into the tank 6. The electrolytic water generator 7 dissolves hydrogen in the water containing the reverse osmosis water 25 introduced from the tank 6.
