The Salmson 2, military designation Salmson 2 A2 was a French biplane reconnaissance aircraft made by Salmson. It was developed to a 1916 requirement. Along with the Breguet 14, it was the main reconnaissance aircraft in use with the French army and the American Expeditionary Force's aviation units in 1918. At the end of the First World War, one-third of French reconnaissance aircraft were Salmson 2s. 
A later variation of the plane, called the Salmson 4, was an enlarged version fitted with light armour, which was designed to meet the Ab 2 ground attack role. It had limited production in 1918, but was cancelled at the end of the war.