Cumene oxidation was studied in the solution of benzonitrile or its mixture with chlorobenzene in the presence of tetracthylammonium chloride at 358 K. The best linear correlation (R = 0.997-0.999) between oxygen uptake ([O-2]) and time (t) was found to be in [O-2] - t(1/2) coordinates. An oxidation scheme was suggested which includes the reversible reaction of equilibrium formation of the 1 : 1 salt-hydroperoxide complex whose subsequent degradation results in radical generation and a salt deactivation reaction by bimolecular interaction between the complexes. Mathematical simulation of this scheme with an appropriate system of differential equations and its solving show that the scheme satisfactorily describes the principal quantitative kinetic features of the process.