Liquid-phase air oxidation of cyclohexane to cyclohexanone and cyclohexanol with cobalt napthenate as catalyst was carried out in a continuous bubble column reactor. The effects of reaction conditions including temperature, pressure, residence time of cyclohexane, superficial air velocity and catalyst concentration on cyclohexane conversion and the selectivities to cyclohexanone, cyclohexanol and cyclohexanyl hydroperoxide were studied. When the reaction was conducted in the system temperature range from 413 to 423 K, system pressure range from 1.2 to 1.5 MPa, superficial air velocity range from 2.5 to 3.5 cm/s and cyclohexane residence time of 30~40 min, the cyclohexane conversion of 5%~7% and the total selectivity to cyclohexanone, cyclohexanol and cyclohexanyl hydroperoxide of 80%~85% were obtained.