A catalyst composition, a method from preparing an olefin polymer using the same, and an olefin polymer prepared from the same are disclosed herein. In some embodiments, a catalyst composition includes a first metallocene compound represented by the Chemical Formula 1, a second metallocene compound represented by the Chemical Formula 2, and a support. The catalyst composition can exhibit high activity in an olefin polymerization reaction and thus contribute to reducing catalyst costs, and can also exhibit high copolymerizability which can secure excellent processability and long-term physical properties, and thus, is suitable for providing polymers for pipes.