The novel cadmium molybdenum phosphorous (CdMoP) series composite oxide catalyst was prepared by ionic liquid thermal synthesi, and the physicochemical properties of the catalysts were characterized by FT-IR, XRD, SEM, TEM and XPS. The characterization results show that the ionic liquid can not only enter the framework of the CdPMo-80 catalyst, but also fix the P element in the catalyst, thus presenting an orderly growth layered structure and having more strong acid centers. The catalytic performance of the CdMoP-80 composite metal oxide catalyst was investigated by using cyclohexene oxidation to prepare cyclohexane oxide as a probe reaction. The results indicated that the product was qualitatively and quantitatively analyzed after reacting for 4 hours at 55 oC with a catalyst dosage of 0.2 g, 4 mL of 30% hydrogen peroxide, 2 mL of cyclohexene, and 4 mL of acetonitrile. The conversion rate of cyclohexene was 99.2%, and the selectivity of cyclohexene oxide was 97.0%.