The XXVI Reserve Corps () was a corps-level command of the German army during World War I.
XXVI Reserve Corps was formed in October 1914. It was part of the first wave of new Corps formed at the outset of World War I consisting of XXII - XXVII Reserve Corps of 43rd - 54th Reserve Divisions (plus 6th Bavarian Reserve Division). The personnel was predominantly made up of (wartime volunteers) who did not wait to be called up. It was still in existence at the end of the war in the 18th Army, on the Western Front.
On formation in October 1914, XXVI Reserve Corps consisted of two divisions. but was weaker than an Active Corps
In summary, XXVI Reserve Corps mobilised with 26 infantry battalions, 8 machine gun platoons (16 machine guns), 2 cavalry detachments, 18 field artillery batteries (72 guns) and 2 pioneer companies.
XXVI Reserve Corps had the following commanders during its existence: