Abstract: There are provided a method of and an apparatus for producing ultrafine metal compound particles. An electrolytic bath having an anode and a cathode is partitioned into chambers by at least one ion exchange layer. An electrolytic solution containing metal ions as a starting material for the ultrafine metal compound particles is contained in a chamber on the anodic side of one ion exchange layer, and an alkaline electrolytic solution is contained in a chamber on the cathodic side of the ion exchange layer. When a voltage is applied between the anode and the cathode, the metal ions transfer from the anodic side chamber to the cathodic side chamber through the ion exchange layer, whereby ultrafine metal compound particles are precipitated in the alkaline electrolytic solution in the cathodic side chamber.