Aiming at the low prediction accuracy on formation pore pressure, high requirements of casing program design, abnormal pressure at low temperature and narrow security window of drilling fluid density in deepwater drilling process in Southeast Hainan basin, through the regional formation pressure prediction method and based on the research and practice of key technologies of casing program optimization design, drilling fluid technology optimization, surface casing cementing technology optimization and annular trapped pressure control technology, a set of key technology system suitable for deepwater drilling in this region is formed and has been successfully applied in deep wells drilling operation in recent years with high drilling efficiency, low accident rate and reasonable cost.