A study has been made of the physicochemical properties of catalytic systems and the mechanism of oxidation of cumene by molecular oxygen in inverse micellar solutions of copper(II) alkanoates with a normal hydrocarbon chain ((R-COO)2Cu, where R = -C16H33, -C12H25, -C9H19, -C4H9) and in inverse micellar solutions of cetyltrimethylammoniumbromide (CTMAB) containing solubilized CuBr2. It has been found that the formation of spherical premicellar associates below the critical concentration of micelle formation (CCM) and of lamellar micelles above the CCM leads to lower activity of the catalyst and selectivity of formation of hydroperoxide. It has been demonstrated that the reduction in catalytic activity and the change in the properties of the catalyst are due to the formation of cluster Cu(II) complexes in the inverse micellar phase.