The newest generation of nuclear reactors (GEN IV) with a planned outlet temperature up to 500°C or even higher, require materials with higher radiation and thermal resistant than those used in current reactors. Some also require high corrosion resistance in different cooling media such as supercritical water, molten salt, etc. Research and development of materials for construction have run alongside the development of the reactors, however the final decision about the material for some components is still missing. This paper gives an overview of the most perspective materials for the GEN IV reactors., Jana Veterníková., and Obsahuje bibliografii