Abstract: Disclosed are a polymer for ultra-high strength concrete admixture and a method for preparing the same, more specifically, a polymer for ultra-high strength concrete admixture prepared by polymerizing two or more copolymers based on unsaturated organic monomers having urethane derivatives, and and a method for preparing the same. Also, the concrete admixture comprising the polymer exhibits high water-reducing ability, thus improving workability and strength of the concrete composition. In addition, the concrete admixture exhibits defoaming capability, thus enabling easy control of air amount of the concrete composition without using any defoaming agent.