A sacrificial positive electrode material, a positive electrode comprising the same, and a lithium secondary battery having the positive electrode are disclosed herein. In some embodiments, a sacrificial positive electrode material includes a lithium cobalt oxide represented by the following Chemical Formula 1, wherein the sacrificial positive electrode active material has a defect formation energy of metal (M) of −4.0 to −8.5 eV, calculated using density functional theory (DFT): LixCo(1-y)MyO4   [Chemical Formula 1] M is at least one selected from the group consisting of Al, Fe, Zn, Ti, W, Mg, Ge and Si, pa x and y are 5≤x≤7 and 0.05≤y≤0.6. When the defect formation energy of the metal is controlled within a specific range, a high initial charging/discharging efficiency is realized during initial charging/discharging, and the amount of gas additionally generated at the later time of charging/discharging is reduced. Thus, stability and the charging/discharging performance of a battery is improved.