The work aims to extend the application range of polyepoxysuccinic acid (PESA) by synthesizing polyepoxy succinic acid derivatives (IA-PESA), so as to improve the anti-scale and corrosion performance of PESA. Epoxysuccinic acid (ESA) and polyepoxysuccinic acid (PESA) were synthesized by anhydride, IA-PESA was prepared by polymerization of ESA and itaconic acid (IA) and then the scale inhibition and corrosion inhibition properties of IA-PESA were studied. PESA and IA-PESA were characterized by FT-IR. The molecular weights of PESA and IA-PESA were measured by viscosity method. In static scale inhibition experiment, the scale inhibition rate to CaCO3 was over 90% above and that for CaSO4 was as high as 95% or even 100% under certain experimental conditions. The performances of IA-PESA dispersed Fe(III) and stable Zn2+ were significantly better than those of PESA. In static weightless experiments, when the dosage of IA-PESA and PESA were 150 mg/L, the corrosion rate of IA-PESA was significantly lower than that of PESA. From the results of SEM studies of calcium scale and corrosion specimens, CaCO3 and CaSO4 with high density and lattice structure were changed into loose and irregular crystal structure with low density by IA-PESA. The SEM of corrosion specimens proved that uniform corrosion and pitting had disap-peared and the surface was smooth. Under the same test conditions, the scale inhibition, corrosion inhibition, dispersing Fe(III) and zinc stabilization of IA-PESA are better than those of PESA. IA-PESA changes the crystal structure of calcium scale on the surface of the equipment and reduces the corrosion under the scale, thus playing a significant role in corrosion inhibition.