Tsunamis are one of the most destructive and deadly natural phenomena in the world. Tsunamis can result from earthquakes, volcanic eruptions, or underwater landslides that cause huge waves that hit the coast and destroy everything in their path. Analysis of the global impact of devastating tsunamis shows various aspects that need to be understood to better anticipate this disaster. The social impact caused by the tsunami was very significant. Communities located along the coast are often the most affected. Loss of life, destruction of infrastructure, and psychological trauma are the main challenges. Meanwhile, population migration due to this disaster can cause pressure on new areas of destination. In the economic aspect, the tsunami not only destroyed property, but also created ongoing effects in the local industrial cycle. The tourism sector often experiences heavy losses, and this can affect the regional economy in the long term. For example, a decrease in tourist visits to areas frequently hit by tsunamis can hamper economic growth and create unemployment. From an environmental perspective, tsunamis can cause severe damage to marine and coastal ecosystems. Coral reef destruction and habitat changes are causing the decline of endangered species. In addition, water pollution due to spills of hazardous materials can worsen the condition of marine biomes. The tsunami also had an impact on global policies related to disaster mitigation. Increasing investment in early warning systems and more disaster-resilient infrastructure is a key focus. Affected countries are increasingly engaging with the international community, as well as further research into risk management technologies and strategies. One strong example of global impact occurred after the Indian Ocean tsunami in 2004. The disaster claimed more than 230,000 lives and changed the way the world views disaster mitigation. Building a more efficient tsunami warning system and training local communities are priorities to reduce future risks. Furthermore, international collaboration in tsunami research and resources helps reduce long-term impacts. Global conferences, such as the “World Conference on Disaster Risk Reduction,” are an important means of sharing best practices and the latest technology in tsunami mitigation and response. Finally, climate change can worsen the impact of tsunamis. Sea level rise can increase the vulnerability of coastal areas to large waves. Therefore, it is very important to include climate change considerations in the planning and development of mitigation policies. By considering all these aspects—social, economic, environmental, and global policy—we can understand the broad impact of tsunamis and how we can be better prepared to face and mitigate these disasters in the future.