An ice-making water purifier includes a water tank unit, an instantaneous heating device, an extraction member, an ice-maker, a supply pump, an ice-making water inlet passage, an ice-making water supply valve, a flow rate sensor, and a controller configured to control driving of the supply pump and the opening and closing of the ice-making water supply valve such that purified water corresponding to a predetermined supply amount of ice-making water is supplied to the ice-maker on the basis of a flow rate value measured by the flow rate sensor. The controller controls the opening and closing of the channel such that purified water is preferentially supplied to the instantaneous heating device among the instantaneous heating device and the ice-maker.