The highly efficient and selective photocatalytic oxidation of cyclohexene with molecular oxygen under mild conditions is an important objective in chemical synthesis. In this work, a pure inorganic framework CoMo was self-assembly prepared under solvothermal conditions by incorporating simple MoO42-, cobalt (II) ion. The catalyst CoMo was well characterized by infrared spectroscopy (FTIR), nitrogen adsorption-desorption, powder X-ray diffraction (XRD), scanning electron spectroscopy (SEM), and X-ray photoelectron spectroscopy (XPS) methods. It displayed high efficiency and selectivity in the photocatalytic oxidation of cyclohexene to 2-cyclohexen-1-ol in O-2 atmosphere. The influence of solvents, oxidants, pressure of oxygen, reaction temperature, light source and time on the reaction was investigated. More interestingly, the selectivity of the reaction in 4-ethyltoluene was much higher than that in other solvents.