The present invention relates to a method of producing a cobalt-coated precursor, the cobalt-coated precursor produced by the method and a positive electrode active material for a lithium secondary battery, the positive electrode active material which is prepared using the cobalt-coated precursor and, more particularly, to a method of preparing a new positive electrode active material having improved high capacity and stability by coating cobalt on the surface of a precursor in the precursor step, thereby improving characteristics of the precursor degraded when washed with water, and a positive electrode active material prepared by the method.