When deep-sea cementing is performed in the natural gas hydrate formation， hydration heat release of cement slurry will change the phase transition equilibrium conditions of hydrate， and induce hydrate decomposition， causing the quality of cementation at the two interfaces to decrease. In order to improve the cementing quality in hydrate formation， phase change microcapsules with endothermic temperature control can be added to cement slurry to effectively reduce the hydration temperature of cementing slurry. Based on this， a temperature-controlled microcapsule for cementing slurry in deep water hydrate formation was prepared with the self-assembly method. The temperature-controlled core material with single phase transition temperature is easy to fail due to the complex external temperature environment of cementing cement slurry in the process of reaching hydrate formation. For expanding the temperature control range， paraffin and white oil were selected as the mixed core material with the temperature control range from 14.8℃ to 39.8℃ achieved. Study shows that the microcapsule has good apparent morphology and no agglomeration with each other， so it is not prone to leakage during thermal cycling. After mixed with cement slurry， it doesn’t affect obviously the rheological properties of cement slurry. At low dosage， microcapsules mainly reduces the peak temperature of cement slurry and improves the overall mechanical strength of cement stone. At high dosage， microcapsules can not only effectively reduce the peak temperature of cement slurry， but also delay the heat release rate of cement slurry.