To supply ionic water not contaminated by various bacteria by electrolyzing water in an electrolytic cell formed from a resin material having an antibacterial agent to form ionic water.

An electrolytic cell 1 is formed by molding a resin material kneaded with an antibacterial agent 2 such as a silver type antibacterial agent e.g. silver or silver sulfonate or a copper type antibacterial agent e.g. a composite of copper or copper sulfate-containing regenerated cellulose with polyacrylonitrile copper sulfide or a phenolic cooper chelate resin. Water is supplied to this electrolytic cell 1 from a water inlet 24 and voltage is applied across a cathode 20 and an anode 30 to electrolyze the water supplied to the electrolytic cell 1 and acidic ionic water is formed in an anode chamber 6 and alkali water is formed in a cathode chamber 5. By this constitution, the propagation of various bacteria in the electrolytic cell 1 is prevented to prevent that ionic water is contaminated by various bacteria.