After earning a degree in physics at Tohoku University in Sendai, Japan, Sumio Iijima moved to Arizona State University as a post-doctoral associate where he initiated high-resolution transmission electron microscopy (HRTEM) (1970-1982). Using the technique, he has brought a new type of information of local atomic structures of crystals into condensed matter physics, solid state chemistry, crystallography, mineralogy and materials science. Ample experiences with the different types of materials including nanostructures of carbon materials have led him to discover carbon nanotubes in later years. In these days the technique has been known as the most powerful one in the research fields of nano-materials science and nanotechnology. In 1982 he returned to Japan and worked for 5 years on a national ERATO project on nano-particles, then joined the NEC fundamental research laboratories. In 1991 he discovered carbon nanotubes that have initiated nano-materials science and nanotechnology and has being attracted world-wide researchers in academia and industry. Following the discovery, he has been honored with numerous awards and prizes that include: Franklin Medal in physics (2001), Agilent Europhysics award (2002), Balzan Prize (2007, Italy-Switzerland), Kavli Prize (Norway, 2008), Prince of Asturias Award (Spain, 2008), Order of Culture (Japan, 2009), He is members of Foreign Associate of the National Academy of Science (USA. 2007), the Norwegian Academy of Science and Letters (2009), member of Japan Academy (2010) and foreign member of Chinese Academy of Sciences (2011).