A manufacturing method of a cathode active material for lithium secondary battery, including: preparing a first solution by mixing a metal oxide and a solvent; preparing a metal-mixed solution by adding an acidic solution to the first solution and then applying ultrasonic waves to the mixture; centrifuging the metal-mixed solution; preparing a second solution by mixing a supernatant of the centrifuged metal-mixed solution, a reductant, and a solvent and then applying ultrasonic waves to the mixture; obtaining powder by filtering and then drying the second solution; forming mesoporous spherical nanoparticles by mixing the powder, a metal, a lithium precursor, and a solvent, applying ultrasonic waves to the mixture and then drying the mixture; and performing a heat treatment to the spherical nanoparticles, and a cathode active material for a lithium secondary battery obtained by the manufacturing method. The cathode active material for lithium secondary battery is mesoporous spherical nanoparticles.