Abstract: An adsorbent, which has been prepared by mixing (a) one part by weight of (i) at least one member selected from the group consisting of hydrated ferrites of titanium, zirconium and tin or (ii) a mixture of the said hydrated ferrites(s) and at least one member selected from the group consisting of hydrated oxides of titanium, zirconium, tin and iron with (b) about 1/10 to 3 parts by weight of a thermosetting resin showing resistance to acids and alkalis such as an unsaturated polyester or polyurethane resin, followed by curing.The adsorbent can be used to adsorb a great variety of anions and cations and especially as an adsorbent for phosphate ions.The adsorbent shows excellent resistance to acids and alkalis, and can be subjected to repeated desorption and regeneration procedures without causing any deterioration of its adsorptive capacity, thus permitting its repeated usage over a long period of time.The adsorbent can be magnetically separated, and facilitates solid-liquid separation.