Wildfires threaten human lives and ecosystems and have a significant impact on the economy. Greece is one of the most vulnerable countries in the world with respect to wildfires. The purpose of this article is to assess the climate change impact of wildfires on the ecosystems of Greece and to determine areas where prevention measures should be utilized. To achieve this, the variability of the Fire Weather Index (FWI) is examined under the RCP4.5 and RCP8.5 scenarios from 2022 to 2098. The Greek ecosystems are selected based on the vegetation zones that cover the Greek domain. Under both scenarios, a significant intensification of fire weather is observed which will increase the likelihood of severe wildfires occurring in various types of ecosystems in Greece. The worst affected areas are southern and eastern Greece provided that they have sufficient fuel. The results are more pronounced for the RCP8.5, especially after mid-century. By the end of the century, most ecosystems will be prone to intense fire activity under RCP8.5, and for example, the “Mediterranean coniferous forests” in high altitudes could face extinction. Even under the milder RCP4.5 scenario, high-intensity wildfires are projected to occur with increasing frequency in places that are currently rare. This project highlights the necessity of climate change mitigation and the employment of more effective and widespread prevention and firefighting methods. The management of currently fire-prone areas should be emphasized but the state must be prepared to face extreme fire incidents in a broader range of ecosystems including mid-altitude and even high-altitude forests.