Konstantinos Kallaris (Greek: Κωνσταντίνος Καλλάρης; 1858–1940) was a senior Hellenic Army officer who distinguished himself in the Balkan Wars of 1912–1913.

[1] In early 1911 he was placed as commander of the 2nd Infantry Division at Athens, which quickly became a model formation under the supervision of the French military mission to Greece.

Kallaris led the 2nd Division in the Second Balkan War as well, first in the attack against the Bulgarian garrison in Thessaloniki and thereafter in the battles of Kilkis and Kresna.

[1] In 1914, promoted to Lieutenant General, he assumed command of the newly established I Army Corps.

He served briefly as Minister of Military Affairs in the summer of 1916, and retired from service on 29 June 1918.