Allyl-beta-cyclodextrin is utilized to react with dimethyl diallyl ammonium chloride and acrylamide to synthesize a novel water-soluble cationic polymer by redox free-radical polymerization. The optimum polymerization conditions are determined by the single-variable method, while the structure is characterized by Fourier transform infrared and scanning electron microscopy. In rheological experiments the polymer demonstrates superior properties compared to polyacrylamide. Interfacial tension and adsorption experiments prove the excellent performance of the polymer which can effectively decrease the interfacial tension and reduce the surfactant loss caused by stratum absorption in the process of polymer/surfactant flooding, thus indicating the potential application of the polymer for enhancing oil recovery.