To provide an ionized water generating device free from the contamination of bacteria even after the lapse of several hours from the stoppage of water supply, for example, in the case of intaking water in the next morning after one night and capable of obtaining the generated water having an adequate ion concentration.

This ionized water generating device is constituted of an electrolytic cell 3 generating an alkaline ionized water and an acidic ionized water by electrolyzing water, a water pipe 31 of a water discharge passage for discharging one of the ionized waters generated in the electrolytic cell 3 as the generated water and a water pipe 32 of a waste water passage for discharging another ionized water as a waste water. Further, the water pipe 31 is provided with a stop valve 35 for passing the generated water by opening at the time of water supply and for interrupting the flow-in of the generated water and air by closing at the time of stopping the water supply.