介绍日本地下空间涝灾历史与防洪涝政策。分析地下空间涝灾事故发生的原因，包括地下空间敞口处涝水漫溢导致地下空间进水、无法及时有效地排水导致地下空间积水、地下空间疏散困难导致救援困难。通过文献和工程设计文件阅读的方法，总结归纳出: 1)日本为抵御洪涝灾害提出了一套完整的地下空间防洪排涝设计体系，包含提出敞口防进水措施、优化排水蓄水设计、提高建筑空间应灾性; 2)在出入口、通风口、下沉广场、采光井等敞口安装各类挡水措施可从“源头”有效防水，并且根据敞口的进水时间和进水程度选择合适的挡水对策； 3）建设城市级排水系统、地下空间储水设施可防止地下空间积水； 4）良好的地下空间设计可以有效避免疏散困难所带来的事故。为应对近年来全球性气候变化所带来的洪涝灾害，建议从源头防水、过程治理、工程应用3个方面形成完善的防灾体系，有效提高地下空间的防洪排涝能力。

In this study, the flood prevention design methods for underground space in Japan are explored by providing a historical background on waterlogging in underground spaces and flood control policies in Japan. Then, the causes of waterlogging accidents in underground spaces are analyzed, including water overflow at the opening of the underground space, ineffective drainage leading to water accumulation, and evacuation difficulties during rescue efforts. Through an examination of literature and engineering design documents, the authors conclude that a comprehensive underground space flood control and drainage design system proposed by Japan can resist flood disasters. This system includes measures to prevent open water inflow, optimize drainage and water storage design, and improve disaster response within building spaces. It is also found that the installation of various waterretaining measures at entrances, vents, sunken squares, lighting wells, and other openings can effectively waterproof from the "source". Additionally, appropriate waterretaining measures can be selected based on the water inflow time and degree of the opening. Furthermore, the construction of urban drainage systems and underground water storage facilities can prevent water accumulation in underground spaces. Favorable underground space design can also effectively avoid accidents caused by evacuation difficulties. To cope with the flood disasters caused by global climate change, the authors suggest forming a complete disaster prevention system from three aspects: source waterproofing, process control, and engineering application. This comprehensive approach can effectively improve the flood control and drainage capacity of underground spaces.