A method of producing, in a liquid, a hollow particulate material having a cavity therein, the method including: (A) blowing gas into a resin solution containing a first dispersion medium; (B) pouring the resin solution to which the gas is blown in step (A) into a second dispersion medium to form liquid droplets encapsulating the gas and prepare a dispersion of the liquid droplets; and (C) solidifying the liquid droplets formed in step (B) and isolating the solidified liquid droplets from the second dispersion medium.