The Basic Guidelines for Sediment Disaster Prevention are established by the Minister of Land, Infrastructure, Transport and Tourism under Article 3 of Sediment Disaster Prevention Act (Act No. 57 of 2000). Since its initial establishment in 2001, the Basic Guidelines have undergone successive revisions to deal with problems identified in major sediment disasters that occurred in this century. Now the Basic Guidelines clarify nature of sediment disaster and principles of its prevention, and detail wide variety of prevention measures under the Act. They include precautionary measures such as planning of warning and evacuation system, and emergency operational measures such as orientation and support of evacuation behavior. Some of the provisions of the Basic Guidelines are not positively delegated by the Act, but no less important. The Basic Guidelines play a central role in sediment disaster prevention policy in Japan and their importance will not cease to grow in the climate‐change era.