结合南水北调工程情况，介绍了水工建筑物及电气设备的防雷设计原则是针对雷击原因采用了3级保护，即直接接闪将雷电引入地下泄散、防止雷电波侵入和限制设备上浪涌过电压幅值。防护措施主要采取了分流、均压、屏蔽、接地、箝位保护等5项措施。防雷设计中尽量采用自然接地体、辅以人工接地体，以节省投资。对渡槽、启闭机室、降压站等都设置了两层或三层接地网形成屏蔽笼，把建筑物或设备保护起来，并做好接地，确保雷电泄放畅通。

Based on the condition of the South-to-North Water Diversion Project, this paper introduces the lightning protection principles of hydrostructure and electrical equipments according to the reasons of lightning from three aspects, namely using air-termination and earth-termination system to discharge lightning current, protecting against lightning surging on incoming services and limiting over-voltage on equipments. There are five primary protection measures: distributaries, voltage sharing, shield, grounding and clamp protection. In the design of lightning protection, natural earth electrode is adopted with priority supplemented by artificial earth electrode in order to reduce the cost. Double or treble-deck grounding grid is designed for flumes, hoist chambers, transformer substations and other buildings so as to protect the equipments and discharge lightning current through grounding.