The Islamic Republic of Iran participated in Russia Nanotechnology Exhibition (RUSNANOTECH 2011) for the fourth successive year.This exhibition is known as the largest annual exhibition event in Russia in the field of nanotechnology that is organized by RusNano, and many countries and companies from the private sector participate in it. In the last three years, a number of the Iranian companies who owned technology or product in the field of nanotechnology took part in this exhibition under the united identity Iran Nano. This year, four Iranian companies with 11 nanotechnology based products presented their achievements in a stall with an area of approximately 60 square meters. The participation of Iran in such exhibitions alongside the countries active in the field of nanotechnology helps introducing the progresses and capabilities of Iran to other countries. In addition, it has caused the Iranian researchers and technologists to believe that they can present new plans in the scientific world by comparing their achievements with those of the well-known countries. Most of the stalls in this exhibition belonged to the companies, parks, and scientific and research centers from Russia. Among the other countries who participated in RUSNANOTECH 2011 and put on display their achievements in125 stalls, mention can be made of Iran, Germany, Finland, Spain, the United States, Japan, England, Australia and the Netherlands.