Nanostructured materials have been an important subject in research since the late 1980s.There are many methods developed for synthesis of nanopartieles such as ball-milling, precipitation, hydrothermal method, chemical vapor deposition and so on.Different from conventional methods, we have been studying synthesis of metallic, semiconductive and ceramic nanomaterials by DC arc and RF plasma methods.Recently we investigated synthesis and properties of nanostructured hydrogen storage materials and silicon oxynitrides by hydrogen plasma metal reaction (HPMR) and RF cold plasma, respectively.