In contemporary Middle East politics, Iran and Turkey are the two important countries. The two countries are among the ancient civilisations and are also old competitors for playing a dominant role in the Middle East power structure as well. Further the US invasion of Afghanistan and Iraq in 2001 and 2003 added extra fuel to their competition by created a power vacuum in the power structure of the region. However despite ideological differences between the two countries maintained peaceful relations as there are certain concerns like geopolitical realities and economic interests, energy, Iran’s isolation in world politics due to US led sanctions etc that compelled the two nations to work together. Even Turkey played very active role in mediating between Iran and US for resolving the Iranian nuclear issue peacefully. However the upspring in Middles Eastern countries once again brought their difference to forefront particularly with respect to ongoing Syrian crisis. Both the countries alleged one another for adding fuel to the crises in the region in order to safeguard their national interests. In this situation of uncertainties, this paper would try to look into the changing nature of Iran-Turkey relationship in post 9/11 era and try to analyse and pinpoint the areas of competition between the two countries and its effects on regional peace and stability.