The present invention provides a method of manufacturing a positive electrode active material for a lithium ion secondary battery. The method includes a water-washing step of washing a lithium-nickel composite oxide containing lithium (Li), nickel (Ni), and an element M (M) (wherein, the element M is at least one element selected from Mn, V, Mg, Mo, Nb, T, Co, and Al) with water, and conducting a filtration to form a washed cake; a filling step of filling, the washed cake which is a material to be dried and a tungsten compound without lithium into a dryer; and a drying step of drying the material to be dried by the dryer with flowing, wherein the filling step includes a time period in which the washed cake and the tungsten compound without lithium are supplied to the dryer at the same time.