A Prospect of researches of volcanoes is given from the stand point of energetics of the earth’s interior. Volcanism is not an important mechanism for the energy transfer from the interior, while it is the major process of crustal formation, To test the hypothesis of mantle differentiation, the researches of continental plateau basalt may be crucial. Two types of tectonic activity, the growth of the Asian continent and the development of the Pacific Ocean, should be distinguished to clarify the volcanism in the Japanese Islands area. A research of lunar volucanism is proposed in relation to the terrestrial volcanism.