Gas hydrate is a potential clean resource. There are strong conditions in Mohe permafrost region for gas hydrate formation. According to the local geological conditions and the technical requirements of hydrate exploration and development, the appropriate borehole structures and drilling parameters were determined, and drilling equipments were rationally selected. Low-temperature drilling mud, drilling mud cooling technology and large diameter wire-line coring drilling were applied in drilling process for rapid coring to reduce the decomposition of gas hydrate. The paper described the key technologies of drilling construction for gas hydrate in Mohe permafrost region.