Introduction With the collapse of Soviet Union in 1991, the tensions between the East and the West have come to an end and the whole world hah an idea that the bad days is over. But the events that began in Ukraine in the 2013 brought some question in the literature such as is it the beginning of the new Cold War? Especially, with the election of the Putin in 2000, Russia started to follow a more active foreign policy to increase its influence in the post-Soviet area. Within that framework, Russia has tried to diminish the influence of the EU and NATO in its neighboring countries and has not hesitated to use hard power when necessary to do so. Annexation of Crimea has been linked to this policy, and Russia has shown that it will not compromise containing from the West. That’s why the Ukrainian crisis was considered one of the most serious crisis which threatened the international system after the end of the Cold War (Himmelreich, 2014) because it was the first time when one European state had seized territory from another country by using its military power. The crisis has brought the Russian threat, which European states have forgotten for many years, back to the agenda. At the end of the day, the West has come to realize that they have to re-examine their Russian policies. Indeed, both Russia and the West involved more and more in the conflict, because both side have the same fear: if one side wins, the others influence in Ukraine would be gone. (Studienumber & Submission, 2016). Today, there years after the crisis, with one exception, Russia, Crimea is isolated from the whole world. Economic sanctions against both Crimea and the Russian Federation are still in force. Additionally, the Russia was suspended from the Group of Eight (G8) after the annexation of Crimea. In addition, since the Cold War between Russia and the West, today relations are reached the lowest point and the pragmatic competition between the parties has turned into confrontation.” (Bordachev, 2016). In this paper, it will be discussed that how the West and Russia’s diverse security perceptions showed itself in the Crimean Crises and how they reacted to Crimea in the name of their national interest. It will be focused on how Russia reads the annexation of Crimea and it will be argued the external causes of the annexation of Crimea caused mainly because of geopolitical controversy between Russia and the West, and diverse security concepts between the parties.1. Background of Crimea Crisis When the date shows November 21, 2013, President Viktor Yanukovych, made a surprise announcement that Ukraine would not continue to negotiate with European Union and will suspend their involvement in the EU’s Association Agreement in order to pursue closer relations with Russia. More surprisingly, a month later, Yanukovych and Putin announced the signing of an action plan between Ukraine and Russia in which Russia would give a $15 billion loan and a gas price discount to Ukraine in return for Ukraine’s promise not to pursue deeper ties with the EU. This surprising U-turn by Yanukovych had started a popular unrest, and in 18 February 2014, the Euromaidan movement started with thousands of protestors who gathered on Kiev’s Maidan square, expressing their anger to Yanukovych postponed the signing of a Ukraine–European Union Association Agreement. According to Moscow, the demonstrations were supported by the West in order to revise the decision of Yanukovych. Russia went further and declared that the Western politicians should not interfere in the internal affairs of Ukraine (Studienumber & Submission, 2016). However, for many Ukrainians, it was not the same case. Most of the Ukrainians have a faith that Association Agreement was a step stone for the modernization for their country (Halling & Stewart, 2014). They saw the EU as their future, and their protests did not stop even after the government’ brutal response to their own citizens. Rather than giving up, the protests grew, and eventually led to the overthrown of pro-Russian leader Viktor Yanukovych. After Yanukovych fled the country, the new regime was established in Ukraine. However, newly established government quickly showed that they had no interest in a cooperation with Russia would seek a rapid integration with the EU. This reflected that getting the Ukraine in Moscow’s orbit failed, and this time Russian response became more accurate. Russian tried to get benefits from the situation which Ukraine was in, and the Russian government called for a referendum vote for annexation of the peninsula. %96.77 of the Crimean population voted for the integration into Russian Federation (Russia Today, 2014). Although the referendum was called illegal by the West, the Russia quickly voted to annex Crimea. After three years, the territory is now under Russian military control and a part of Russia (Barry, 2014). 2. Strategical Importance of Crimea The modern history of Crimean Peninsula started in 1783 when Ottoman and the Russian Empire agreed to recognize Crimea as an independent state with the Treaty of Kuchuk Kainarjai in 1774 (Anderson, 1958: 17). Since then, Crimea has become the home of the Russian Black Sea fleet and the peninsula was regarded as the strategically important for the existence of Russian navy. (Saluschev, 2014) Crimea became part of Ukraine in 1954 when the Crimean region was transformed from the Russian Republic to the Ukrainian Soviet Republic by Nikita Khrushchev. As Kramer stated that the main reason behind Khrushchev attitude was to consolidate the Soviet influence and power over Ukraine (Kramer, 2014). Later, with the collapse of the Soviet Union in 1991, Crimea has gained autonomous status within independent Ukraine. Since the beginning, Crimea has always been an important strategic territory due to its geopolitics and its access to the Black Sea and its position in providing security for Russia (Sasse, 2007). Even after the collapse of the Soviet Union, Russia continue to keep its Black Sea Fleet on the Peninsula for security and geopolitical purposes.