P(AM-NaAA-NIDA) was synthesized by using acrylamide(AM), sodium acrylate (NaAA) and 1-(2-N-acryloylaminoethyl)-2-oleic acid imidazole (NIDA) via redox free-radical copolymerization in the presence of (NH4)2S2O8-NaHSO3 as initiator system. The structure of synthesized copolymer was characterized by FTIR, 1H NMR analysis and intrinsic viscosity measurements. As a consequence, the rheology behavior and salt tolerant of the copolymer was substantially improved compared to partially hydrolyzed polyacrylamide (HPAM). Results showed that the thermal resistance of copolymer could be up to 21.18% at 120 oC compared to that at 30 oC. Core flooding experiments revealed the EOR of P(AM-NaAA-NIDA) could increase up to 17.68%. All the results demonstrated that obtained polymer has prominent performance for potential application in enhance oil recovery.