A military treatise or treatise on war is any work that deals with the "art of war" in some basic aspect. Fundamentally military treatises are treatises on military strategy. Other works may also be included in the definition that, although they deal with other topics, include sensitive information about military matters. These may include, among others, description of specific battles, sieges, general campaigns, reports of military authorities, and commented works about ground or naval battles.

Aelianus Tacticus, also known as Aelian, was a Greek military writer who lived in Rome.