Terrorism is a global and common security issue that threatens the security of individuals and states these days. The Islamic state of Iraq and the Levant (IS/ISIL) terrorist organization that emerged with the Syrian civil war and killing the innocent people with reference to Islam. Some individuals/groups who already have a fundamentalist mindset are radicalized by the influence of some environmental factors and participate in terrorist organizations like IS. In this chapter the situation of radicalism in the Balkan region will be examined by explaining terrorism, radicalism, Islam history and Salafist/Wahhabi movement. It should not be forgotten that terrorism is an act that takes place with the use of violence by the fanatics of every ideology/religion. From this, the main aim should be manage and control the radicalization process of individuals/groups.