The present invention relates to a process for producing a demineralized milk that enables excellent reduction in the amount of monovalent minerals while suppressing any reduction in the amount of divalent minerals, as well as a demineralized milk produced using the above process, a process for producing a cheese and whey from the demineralized milk, and a cheese and whey produced using the above process. In the present invention, a demineralized milk having a significantly reduced amount of monovalent minerals is obtained by passing a raw milk solution through an anion exchange resin in chloride form, and then removing the monovalent minerals contained within the raw milk solution using a membrane separation process. Further, a cheese and whey can be produced by heating the obtained demineralized milk to produce a curd, and then separating the curd from the liquid other than the curd by solid-liquid separation.