A terpolymer AA-HPA-SVS was synthesized from acrylic acid (AA), 2-hydroxypropyl acrylate (HPA) and sodium vinyl sulfonate (SVS) by following a free radical polymerization procedure. The scale and corrosion inhibition efficiency and dispersion ability of the terpolymer were studied. The results showed that the AA-HPA-SVS terpolymer had good antiscaling properties towards calcium carbonate and calcium phosphate, and good dispersion ability towards ferric oxide. The scale inhibiting efficiency of the terpolymer can reach to 95% and 93% for CaCO3 and Ca3(PO4)2 respectively when the dosage was 20mg/L. Its corrosion inhibition efficiency towards carbon steel was improved greatly when sodium molybdate was added. When 150mg/L sodium molybdate dehydrate was added to 20 mg/L terpolymer, the corrosion inhibition rate can reach to 85%.