The purpose of the present invention is to provide a three-pack type dialysis agent with which it is possible to set the total acetic acid ion content in a dialysis fluid at a low value and which is excellent in terms of the storage stability of glucose, etc. and can be reduced in the odor of acetic acid. Therewith, it is possible to prepare a dialysis fluid so that the bicarbonate ion concentration can be changed at will according to need, while the concentrations of trace metal ions such as potassium ions, calcium ions, and magnesium ions are kept constant. The three-pack type dialysis agent comprises agent S comprising sodium chloride, agent B comprising sodium bicarbonate, and agent A containing glucose and an electrolyte ingredient which is neither sodium chloride nor sodium bicarbonate. By making the agent A contain acetic acid and an acetic acid salt and satisfy that the molar ratio of acetic acid/acetic acid salt is 1/(0.5-2), a bicarbonate dialysis fluid having a total acetic acid ion concentration of 2 mEq/L or higher but less than 6 mEq/L can be prepared. This agent A not only is excellent in terms of the stability of the ingredients including glucose but also can be reduced in the odor of acetic acid. According to the three-pack type dialysis agent, by controlling the amounts of the agents S, B, and A to be added when preparing a dialysis fluid, the bicarbonate ion concentration and/or sodium concentration in the dialysis fluid can be also changed.
