Spahis (also spelled as Sipahis, Sepahis or Spakh, in Turkish sipahi) were an elite mounted force within the Six Divisions of Cavalry of the Ottoman Empire. The word Spahi is taken from Persian سپاهی Sipâhi meaning "soldier".

Their duties included, among others, to ride with the sultan on parades and as a mounted bodyguard. In times of peace they were also responsible for collecting taxes. The Spahis was the largest division of the six and was the mounted counterpart to the Janissaries, which always fought on foot. The Sipahis were probably founded during the reign of Mehmed II.

Spahis had an important part in The Auspicious Incident, subjugating the last rebellion of Janissaries in 1826. However, two years later, sultan Mahmud II revoked also their privileges and dismissed them in favor of the more modern army structure.

In the French army certain Algerian, Tunisian and Senegalese cavalry units were also called Spahis. Persian equivalent term was sipahi, which also shares its derivation with sepoy.

Sometimes mixed up with Timariots, an irregular cavalry organized according to a feudal system. Sipahis and Timariots had very few things in common and this is probably a simple misinterpretation among Western historians.