The invention provides a preparation method of a high-compaction density 523-type ternary positive electrode material, and belongs to the technical field of preparation of a lithium ion battery positive electrode material. A high-compaction density and low-pH value lithium nickel cobalt manganate NCM523-type ternary positive electrode is in a spherical shape, grain D50 of secondary agglomeration particle is 10-12 micrometers, and the size of primary single-crystal particle is 1.5-3 micrometers. The preparation method of the high-compaction density 523-type ternary positive electrode material comprises the steps of doping 0.1-1.0% of metal oxide into a mixture of lithium carbonate and a ternary precursor LiNi<0.5>Co<0.2>Mn<0.3>(OH)<2>, performing primary sintering, paste washing, secondarysintering, breakage, iron removal, sieving and mixing, and finally, obtaining an NCM523-type ternary positive electrode material. By the method, the compaction density of the NCM523-type ternary positive electrode material is effectively improved, a pH value is reduced, the compaction density of the prepared NCM523-type ternary positive electrode material is larger than 3.7g / cm<3>, and the pH value is smaller than 10.80.