The world's climatic environment has changed several times throughout history, and world orders have been shaken several times because of massive migrations. Many absolute and mighty empires collapsed under the pressure of unstoppable migrations. However, some scientists are very skeptical about the reasons for climate change. The opposing side claims that, unlike in the past, human activity is to blame for the current climate change. Climate change is a fact whose existence is not disputed, even if its source is debated among scientists. Climate change elements cause conflict over limited resources. People are forced to make decisions under these circumstances. They may stay and compete for limited resources or migrate and seek new resources. People who decide to stay could also move later because fierce resource conflicts can cause security problems like terror or civil wars. We can claim that climate change and mobility have positive correlations, even if they may not be the sole reason. Southeast Asia is one of the most sensitive regions to climate change impacts. Social crises and migration waves in this region are of a nature that deeply concerns Taiwan's national security. This article will first examine the phenomenon of migration and review its theoretical background. Then, migration movements may occur due to climate change in Southeast Asia and its impact on Taiwan.