A novel scale and corrosion inhibitor is synthesized by aqueous quadripolymerization with raw materials such as the itaconic acid (IA)，acrylic acid (AA)， 2-acrylamido-2-methy/L-propanesulfonic acid (AMPS) and methyl methacrylate (MMA). Moreover，the preparation procedures of the inhibitor are optimized by the orthogonal experiments. And，95.3 % of scale efficiency for Ca3(PO4)2 ，the transmission rate of iron oxide is 48%，having very good scaling and dispersing capacity， and 75% for CaCO3 could be obtained by evaluating with national standard method when 20 mg/L and 40 mg/L of this quadripolymer is used respecttively，while corrosion efficiency is 74.3%. The analytical results of the infrared spectrum indicate that the quadripolymer contains such ionic groups as the carboxyl ，ester base and sulfonic acid groups.