Hydrous zirconium oxide (HZO) is an inorganic material with high adsorption activity, widely used thanks to its unique surface chemistry and structural characteristics. Its main uses are hemodialysis; water treatment for phosphorus removal (over 90% removal of low-concentration phosphate at 0.5–10 mg/L), defluorination (adsorption up to 36 mg/g at pH 2–6) and arsenic removal (Langmuir saturation capacity 61 mg/g); removal of Cr(III) from industrial wastewater; composite gel beads with strontium alginate to improve solid–liquid separation efficiency; and use as a catalyst carrier or drug-release material.