Tmutarakan (or Tmutorakan) is a medieval Kievan Rus' principality and trading town that controls the Cimmerian Bosporus, the passage from the Black Sea to the Sea of Azov.

Its site is the ancient Greek colony of Hermonassa.

It is situated on the Taman peninsula, in the present-day Krasnodar Krai of Russia, roughly opposite Kerch.

The Khazar fortress of Tamatarkha (Tamantarkhan) is built on the site in the 7th century and becomes known as Tmutarakan when it comes under Kievan Rus control in the 10th and 11th centuries.