Eando Binder is a pen-name used by two mid-20th-century science fiction authors, Earl Andrew Binder (1904–1965) and his brother Otto Binder (1911–1974). The name is derived from their first initials ("E and O Binder").
Under the Eando name, the Binders wrote some published science fiction, including stories featuring a heroic robot named Adam Link. The first Adam Link story, published in 1939, is titled I, Robot. An unrelated collection of stories by Isaac Asimov, also entitled I, Robot, was published in 1950. The name was chosen by the publisher, against Asimov's wishes.
By 1939, Otto had taken over all of the writing, leaving Earl to act as his literary agent. Under his own name, Otto wrote for the Captain Marvel line of comic books published by Fawcett Comics (1941–1953) and the Superman line for DC Comics (1948–1969), as well as numerous other publishers, with credited stories numbering over 4400. The pen-name Eando Binder is also credited with over 160 comic book stories. Earl Binder worked as a mechanical parts inspector for a "large industrial concern" during the 1930s. Otto Binder attended Crane College in Chicago and told Amazing Stories he was once "an amateur chemist with a home laboratory".