A positive electrode active material for lithium secondary batteries including a lithium composite metal compound containing secondary particles that are aggregates of primary particles which are capable of being doped or dedoped with lithium ions, the positive electrode active material for lithium secondary batteries satisfying all of the following requirements to, the lithium composite metal compound has a crystal structure of α-NaFeO 2 type which is represented by Composition Formula described below, Li[Li x (Ni a Co b Mn c M d) 1-x]O 2... (in Composition Formula, -0.1 ≤ x ≤ 0.2, 0.7 ≤ a < 1, 0 < b ≤ 0.3, 0 ≤ c ≤ 0.2, 0 ≤ d ≤ 0.1 and a + b + c + d = 1 are satisfied, and M represents one or more elements selected from the group consisting of Mg, Ca, Sr, Ba, Zn, B, Al, Ga, Ti, Zr, Ge, Fe, Cu, Cr, V, W, Mo, Sc, Y, La, Nb, Ta, Tc, Ru, Rh, Pd, Ag, Cd, In, and Sn), when the positive electrode active material for lithium secondary batteries is measured in powder X-ray diffraction measurement using CuKα radiation, a ratio A/B of an integrated intensity A of a peak within a range of 2θ = 18.7 ± 1° and an integrated intensity B of a peak within a range of 2θ = 44.4 ± 1° is 1.2 or more, lithium carbonate included the positive electrode active material for lithium secondary batteries with respect to a total mass of the positive electrode active material for lithium secondary batteries is 0.7 mass% or less and lithium hydroxide included the positive electrode active material for lithium secondary batteries with respect to a total mass of the positive electrode active material for lithium secondary batteries is 0.7 mass% or less, and a moisture content of the positive electrode active material for lithium secondary batteries with respect to a total mass of the positive electrode active material for lithium secondary batteries is 1000 ppm or less. the lithium composite metal compound has a crystal structure of α-NaFeO 2 type which is represented by Composition Formula described below, Li[Li x (Ni a Co b Mn c M d) 1-x]O 2... (in Composition Formula, -0.1 ≤ x ≤ 0.2, 0.7 ≤ a < 1, 0 < b ≤ 0.3, 0 ≤ c ≤ 0.2, 0 ≤ d ≤ 0.1 and a + b + c + d = 1 are satisfied, and M represents one or more elements selected from the group consisting of Mg, Ca, Sr, Ba, Zn, B, Al, Ga, Ti, Zr, Ge, Fe, Cu, Cr, V, W, Mo, Sc, Y, La, Nb, Ta, Tc, Ru, Rh, Pd, Ag, Cd, In, and Sn), when the positive electrode active material for lithium secondary batteries is measured in powder X-ray diffraction measurement using CuKα radiation, a ratio A/B of an integrated intensity A of a peak within a range of 2θ = 18.7 ± 1° and an integrated intensity B of a peak within a range of 2θ = 44.4 ± 1° is 1.2 or more, lithium carbonate included the positive electrode active material for lithium secondary batteries with respect to a total mass of the positive electrode active material for lithium secondary batteries is 0.7 mass% or less and lithium hydroxide included the positive electrode active material for lithium secondary batteries with respect to a total mass of the positive electrode active material for lithium secondary batteries is 0.7 mass% or less, and a moisture content of the positive electrode active material for lithium secondary batteries with respect to a total mass of the positive electrode active material for lithium secondary batteries is 1000 ppm or less.