PROBLEM TO BE SOLVED: To provide an arsonic adsorptive regenerated cellulose compact that is good in handleability and has a high adsorptive property to arsonic, and to provide a production method therefor, an arsonic adsorbing material and a water treating material.SOLUTION: The arsenic adsorptive regenerated cellulose compact is a cellulose within which an iron ion complex is contained and the iron ion complex is composed of one or more kinds of support selected from a group consisting of inorganic particles having ion-bonding property and organic polymers having a reactive functional group, and iron ions supported on the support. The arsenic adsorptive regenerated cellulose compact can be produced by adding a liquid dispersion of support into a raw material viscose to prepare a viscose liquid and carrying out the coagulation and regeneration of the viscose liquid, and treating the support-containing viscose rayon compact obtained, with an iron compound. The arsenic adsorbing material and water treating mat
