[Problem] To provide a solid dialysis A agent which is to be used in preparing a bicarbonate dialysis fluid, which enables the setting of a low total acetate ion content in a dialysis fluid, and which exhibits excellent storage stability of glucose or the like and a reduced acetic acid odor.[Solution] A solid dialysis A agent which is to be used in preparing a bicarbonate dialysis fluid, wherein: the solid dialysis A agent contains glucose, acetic acid and an acetate salt; at least a part of a mixture of the acetic acid with the acetate salt is an alkali metal diacetate; and the acetic acid/acetate salt molar ratio is adjusted to 1/0.5 to 1/2. This solid dialysis A agent makes it possible to prepare a bicarbonate dialysis fluid which has a total acetate ion concentration of 2 to less than 6 mEq/L. Further, the dialysis A agent exhibits excellent stability of ingredients and a reduced acetic acid odor.