A cathode active material for lithium secondary battery, which has a layered structure containing nickel, manganese, and cobalt, and is secondary particles formed by aggregation of primary particles, and which secondary particles comprise: a core layer having constant concentrations of nickel, manganese, and cobalt; a concentration gradient layer that is formed on the periphery of the core layer and has a concentration gradient of at least one of nickel, manganese, and cobalt; and a shell layer that is formed on the periphery of the concentration gradient layer and has constant concentrations of nickel, manganese, and cobalt, wherein: a thickness of the concentration gradient layer is from 10 to 500 nm; a thickness of the shell layer is from 10 to 200 nm; and a lithium ion diffusion path in the primary particles is formed in a direction towards the center of the secondary particles, wherein the core layer having constant concentrations of nickel, manganese, and cobalt is represented by the following Formula 1 and the shell layer is represented by the following Formula 2: <Formula 1> Li x Ni 1-a-b-c Co a Mn b Me c O 2-y X y wherein in Formula 1, 0.9≤x≤1.15, 0≤a≤0.10, 0≤b≤0.1, 0≤c≤0.1, 0≤y≤0.1, Me is at least one or more elements selected from the group consisting of Al, Mg, B, P, Ti, Si, Zr, Ba and any combination thereof, and X is at least one or more elements or molecules selected from the group consisting of anions of F, BO 3, and PO 4 and <Formula 2> Li x Ni 1-a-b-c Co a Mn b M ec O 2-y X y wherein in Formula 2, 0.9≤x≤1.15, 0≤a≤0.35, 0≤b≤0.70, 0≤c≤0.20, 0≤y≤0.1, Me is at least one or more elements selected from the group consisting of Al, Mg, B, P, Ti, Si, Zr, Ba and any combination thereof, and X is at least one or more elements or molecules selected from the group consisting of anions of F, BO 3, and PO 4. a core layer having constant concentrations of nickel, manganese, and cobalt; a concentration gradient layer that is formed on the periphery of the core layer and has a concentration gradient of at least one of nickel, manganese, and cobalt; and a shell layer that is formed on the periphery of the concentration gradient layer and has constant concentrations of nickel, manganese, and cobalt, wherein: a thickness of the concentration gradient layer is from 10 to 500 nm; a thickness of the shell layer is from 10 to 200 nm; and a lithium ion diffusion path in the primary particles is formed in a direction towards the center of the secondary particles, wherein the core layer having constant concentrations of nickel, manganese, and cobalt is represented by the following Formula 1 and the shell layer is represented by the following Formula 2: <Formula 1> Li x Ni 1-a-b-c Co a Mn b Me c O 2-y X y wherein in Formula 1, 0.9≤x≤1.15, 0≤a≤0.10, 0≤b≤0.1, 0≤c≤0.1, 0≤y≤0.1, Me is at least one or more elements selected from the group consisting of Al, Mg, B, P, Ti, Si, Zr, Ba and any combination thereof, and X is at least one or more elements or molecules selected from the group consisting of anions of F, BO 3, and PO 4 and <Formula 2> Li x Ni 1-a-b-c Co a Mn b M ec O 2-y X y wherein in Formula 2, 0.9≤x≤1.15, 0≤a≤0.35, 0≤b≤0.70, 0≤c≤0.20, 0≤y≤0.1, Me is at least one or more elements selected from the group consisting of Al, Mg, B, P, Ti, Si, Zr, Ba and any combination thereof, and X is at least one or more elements or molecules selected from the group consisting of anions of F, BO 3, and PO 4. a thickness of the concentration gradient layer is from 10 to 500 nm; a thickness of the shell layer is from 10 to 200 nm; and a lithium ion diffusion path in the primary particles is formed in a direction towards the center of the secondary particles, wherein the core layer having constant concentrations of nickel, manganese, and cobalt is represented by the following Formula 1 and the shell layer is represented by the following Formula 2: <Formula 1> Li x Ni 1-a-b-c Co a Mn b Me c O 2-y X y wherein in Formula 1, 0.9≤x≤1.15, 0≤a≤0.10, 0≤b≤0.1, 0≤c≤0.1, 0≤y≤0.1, Me is at least one or more elements selected from the group consisting of Al, Mg, B, P, Ti, Si, Zr, Ba and any combination thereof, and X is at least one or more elements or molecules selected from the group consisting of anions of F, BO 3, and PO 4 and <Formula 2> Li x Ni 1-a-b-c Co a Mn b M ec O 2-y X y wherein in Formula 2, 0.9≤x≤1.15, 0≤a≤0.35, 0≤b≤0.70, 0≤c≤0.20, 0≤y≤0.1, Me is at least one or more elements selected from the group consisting of Al, Mg, B, P, Ti, Si, Zr, Ba and any combination thereof, and X is at least one or more elements or molecules selected from the group consisting of anions of F, BO 3, and PO 4.