To realize an electrolytic water making apparatus capable of making alkaline electrolytic water from raw water using an electrolytic auxiliary agent and capable of replacing a solution of the electrolytic auxiliary agent by a simple method.

A raw water passing part 4a having a second electrode 4b and permitting raw water to pass, an electrolytic auxiliary agent tank 6 having a first electrode 6c arranged therein and housing an auxiliary agent solution 6b in which the electrolytic auxiliary agent is dissolved and an anion exchange membrane 6a are provided. The first and second electrodes 6c and 4b are demarcated by the anion exchange membrane 6a and positive voltage is applied to the first electrode 6c and negative voltage is applied to the second electrode 4b and, when raw water passes through the raw water passing part 4a, anions in raw water are moved to the auxiliary agent solution 6b through the anion exchange membrane 6a to modify raw water to alkaline electrolytic water.