Sadarak (Sədərək) is a rayon of Azerbaijan. It is in the Nakhchivan Autonomous Republic. It was split from the Ilyich rayon (present-day Sharur) in 1990. It has an exclave in Armenia, Karki. Karki came under Armenian control in May 1992. It was captured during the Nagorno-Karabakh War. The capital was Sədərək. It is now Heydarabad.