A continuous method of cumene oxidation in a gas-liquid system is provided, where the liquid phase is represented by cumene and its oxidation products and the gas phase is represented by air. The oxidation process can be carried out either in a reactor series or in a single reactor at least one of which is preferably equipped with at least two airlift-type trays. When specific CHP concentration is achieved, the oxidation products are discharged from the to reaction zone and treated in a mixing device with aqueous ammonia or water to remove organic acids such as formic acid, benzoic acid, etc. and to remove phenol, which is an inhibitor of oxidation reaction. The cumene oxidation product stream, free of organic acids and phenol is recycled to the same reactor in the case of single reactor, or is passed to the next reactor of the series in the case of reactor series. In all cases, the oxidation products treated with water or aqueous ammonia is first directed to a unit for separation of aqueous phase from organic products and then anhydrous organic product stream is forwarded to the next reactor of the series, or recycled to the single reactor for the continued cumene oxidation until the required CHP concentration is achieved. The airlift-type trays in at least one process reactor accelerate the cumene oxidation reaction therein while increasing the process selectivity and enabling the process to be conducted at lower temperature, improving safety thereof. Advantageously, lower quality cumene having impurities such as sulfur-containing trace elements, can be used in the inventive process while maintaining a high process selectivity.