The income of narcotic drugs trading equals to $400 milliard so that it is considered, on the other hand, as the second big economic activity in the world following the gun manufacturing industry. This income, in some cases, comes to the profit drawn of car industry, pharmaceutidcs or banking activities. There is no limit to the narcotic drugs business and it bears almost all borders and nations, as it seems that it is run by multi-national criminal organizations. This business is organized so perfectly and properly that it can control and transfer large quantities of financial resources and hire a considerable number of human resources by spoiling or threatening them. The world confronts with big criminal organizations such as cocaine manufacturers and law-breakers who are ruled over and led by different countries all over the world. This article considers the narcotic drugs market in some European and American countries and brings some facts into consideration such as demand & representation mechanisms and factors influencing on prices. Finally, it reviews the drugs market in Iran.