This article reviews the results in combatting the terrorist organization ISIS in the context of exploring the prospects of postwar order in Syria, as well as geopolitical interests of the regional powers with regards to settlement of the conflict in Syria. The author analyzes Iran’s participation, which since the first days of the conflict was involved in the armed confrontation with ISIS, as well as diplomatic efforts on building inter-Syrian dialogue. Recent events in world politics underlying this research bring the studying of Iran’s interests in settlement of Syrian conflict to mainstream. The goal of this article lies in the analysis of Iran’s geopolitical interests in the Syrian Question through the prism of Iran’s relationship with the key actors involved in de-escalation of the conflict. The conclusion is made that Iran was capable of implementing its strategy for combating ISIS and support the Syrian government largely due to its holistic character, as well as finding strategic allies, including Russia. However, at the current stage of Syrian conflict, there is a disagreement in the positions of multiple strategic partners, which complicates future Syrian stabilization.