Recent research has revealed the peculiar nanoscale effect and edge effect in physical properties of graphene. In addition, the fine processing technology enables us to fabricate the electronic devices based on the nanographenes, and nano-carbon materials are attracting much attention all over the world as a promising key material for the innovative next-generation electronic devices. In this research project, we study the electronic physical properties in the nano-carbon materials, and attempt to design the new electronic/spintronic devices based on nano-carbon with the support of the computational method.