O26

O26 or O-26 may refer to:


 * O26 (text editor), used on Control Data Corporation (CDC) operator consoles
 * Curtiss O-26, an observation aircraft of the United States Army Air Corps
 * HNLMS O 26, a submarine of the Royal Netherlands Navy
 * Lone Pine Airport, in Inyo County, California, United States
 * Oxygen-26, an isotope of oxygen