A method of manufacturing a lithium secondary battery comprising a positive electrode active material, wherein the positive electrode active material comprises one or more lithium transition metal oxides selected from compounds represented by the following Formula 1, activation of the lithium secondary battery is conducted while changing charge/discharge voltage ranges and number of cycles depending on doping amount of M 1 in Formula 1, (1-x)LiM'O 2-y A y - xLi 2-w E w Mn 1-z M 1z O 3-y' A y' wherein M' represents Mn a M b; M represents at least one selected from the group consisting of Ni, Ti, Co, Al, Cu, Fe, Mg, V, B, Cr, Zr, Zn and Period 2 transition metals; M 1 represents at least one selected from the group consisting of Ru, Mo, Nb, Te, Re, Ti, Zr, Ir, Pt, Cr, S, W, Os and Po; E represents an alkali metal; A represents at least one selected from the group consisting of anions of PO 4, BO 3, CO 3, F and NO 3; and 0<x<1; 0≤y≤0.02; 0≤y'≤0.02; 0<z≤0.6; 0≤w≤0.5; 0≤a≤0.5; 0.5≤b≤1.0; and a+b=1, wherein the charge/discharge voltage (V r) range of the activation process satisfies conditions of the following Formula I based on a positive electrode potential, 4.0 − kD r ≤ V r ≤ 4.8 − kD r wherein k represents a voltage drop constant, with the proviso that 0.3≤k≤0.6; and D r represents an amount of M 1 doped (z), and the number of charge/discharge cycles (N r) of the activation is within a range satisfying the conditions of the following Formula III 5 − k ′ D r ≤ N r ≤ 20 − k ′ D r wherein N r represents an integer within the range of the conditions of Formula III; k' represents a cycle reduction constant, with the proviso that 3≤k'≤8; and D r represents an amount of M 1 doped (z). M' represents Mn a M b; M represents at least one selected from the group consisting of Ni, Ti, Co, Al, Cu, Fe, Mg, V, B, Cr, Zr, Zn and Period 2 transition metals; M 1 represents at least one selected from the group consisting of Ru, Mo, Nb, Te, Re, Ti, Zr, Ir, Pt, Cr, S, W, Os and Po; E represents an alkali metal; A represents at least one selected from the group consisting of anions of PO 4, BO 3, CO 3, F and NO 3; and 0<x<1; 0≤y≤0.02; 0≤y'≤0.02; 0<z≤0.6; 0≤w≤0.5; 0≤a≤0.5; 0.5≤b≤1.0; and a+b=1, wherein the charge/discharge voltage (V r) range of the activation process satisfies conditions of the following Formula I based on a positive electrode potential, 4.0 − kD r ≤ V r ≤ 4.8 − kD r wherein k represents a voltage drop constant, with the proviso that 0.3≤k≤0.6; and D r represents an amount of M 1 doped (z), and the number of charge/discharge cycles (N r) of the activation is within a range satisfying the conditions of the following Formula III 5 − k ′ D r ≤ N r ≤ 20 − k ′ D r wherein N r represents an integer within the range of the conditions of Formula III; k' represents a cycle reduction constant, with the proviso that 3≤k'≤8; and D r represents an amount of M 1 doped (z). k represents a voltage drop constant, with the proviso that 0.3≤k≤0.6; and D r represents an amount of M 1 doped (z), and the number of charge/discharge cycles (N r) of the activation is within a range satisfying the conditions of the following Formula III 5 − k ′ D r ≤ N r ≤ 20 − k ′ D r wherein N r represents an integer within the range of the conditions of Formula III; k' represents a cycle reduction constant, with the proviso that 3≤k'≤8; and D r represents an amount of M 1 doped (z). N r represents an integer within the range of the conditions of Formula III; k' represents a cycle reduction constant, with the proviso that 3≤k'≤8; and D r represents an amount of M 1 doped (z).