Abstract: Energizing the oilfield development with digital technology is the megatrend of the advancement of the future petroleum industry. By building the site-scale Internet of Things (IoT), applying artificial intelligence and big data, and creating the three-dimensional digitalized working platform, the Bohai oilfield preliminarily delivered the digital technology-boosted offshore oilfield development mode. Nerve endings of the edge IoT were built to promote full sensing and reliable transfer of the IoT, facilitate data-driven closed-loop smart management of the reservoir, injector-producer, safety, and equipment and facilities, and realize smart operation and maintenance of active offshore production facilities. The onshore-offshore connectivity and operation efficiency were greatly enhanced and the digital technology considerably contributed to the high-quality development of the Bohai oilfield. Moreover, the construction of the smart offshore oilfield was clarified and the outlook of the smart oilfield techniques such as the intelligent digital twin and edge-cloud coordination was presented. This successful trial on building the smart offshore oilfield with the help of digital technology has delivered preliminary achievements and demonstrates tremendous space for future application promotion.