Saudi Arabia and Iran are engaged in a strenuous competition in the Middle East to protect and promote their respective spheres of influence, to each other’s detriment. This qualitative study traces the structural sources of this competition while taking cue from the history. It argues that demise of Saddam Hussein, Iraq’s plunging into civil war, and Arab Spring leading to violent movements in Syria, Libya, Bahrain, and Yemen accentuated Saudi–Iran competition in the region. Study finds that the sources of their rivalry lie at structural level and can be understood by focusing upon their aspiration for the Muslim world leadership, religio-sectarianism, antithetical governance structure, and Iranian nuclear program.