This Safety Report illustrates the diversity of impacts caused by tsunamis and provides an overview of design considerations for nuclear power plants regarding tsunami specific elements. The publication aims to contribute to the enhancement of safety measures for nuclear installations in accordance with IAEA Safety Standards Series No. SSG-68, Design of Nuclear Installations Against External Events Excluding Earthquakes. This Safety Report addresses the elements of design against the design basis tsunami, including design concept, preliminary design and final design, and verification of the design against the beyond design basis tsunami. The intended audience for this publication includes regulators, operators, technical and scientific support organizations, and manufacturers of nuclear installations.