Eric Frank Russell (January 6, 1905 – February 28, 1978) was a British writer best known for his science fiction novels and short stories. Much of his work was first published in the United States, in John W. Campbell's Astounding Science Fiction and other pulp magazines. Russell also wrote horror fiction for Weird Tales and non-fiction articles on Fortean topics. Up to 1955 several of his stories were published under pseudonyms, including Duncan H. Munro and Niall(e) Wilde.

Russell was born in 1905 near Sandhurst in Berkshire, where his father was an instructor at the Royal Military College. Russell became a fan of science fiction and in 1934, while living near Liverpool, he saw a letter in Amazing Stories from Leslie J. Johnson, another reader from the same area. Russell met with Johnson, who encouraged him to embark on a writing career. Together, the two men wrote a novella, "Seeker of Tomorrow", that was published by F. Orlin Tremaine in the July 1937 number of Astounding Stories. Both Russell and Johnson became members of the British Interplanetary Society.

Russell's first novel was Sinister Barrier, cover story for the inaugural, May 1939 issue of Unknown—Astounding's sister magazine devoted to fantasy. It is explicitly a Fortean tale, based on Charles Fort's famous speculation "I think we're property", Russell explains in the foreword. An often-repeated legend has it that Campbell, on receiving the manuscript for Sinister Barrier, created Unknown primarily as a vehicle for the short novel (pp. 9–94). There is no real evidence for this, despite a statement to that effect in the first volume of Isaac Asimov's autobiography, In Memory Yet Green.

His second novel, Dreadful Sanctuary (serialized in Astounding during 1948) is an early example of conspiracy fiction, in which a paranoid delusion of global proportions is perpetuated by a small but powerful secret society.

There are two incompatible accounts of Russell's military service during World War II. The official, well-documented version is that he served with the Royal Air Force, with whom he saw active service in Europe as a member of a Mobile Signals Unit. However, in the introduction to the 1986 Del Rey Books edition of Russell's novel Wasp, Jack L. Chalker states that Russell was too old for active service, and instead worked for Military Intelligence in London, where he "spent the war dreaming up nasty tricks to play against the Germans and Japanese", including Operation Mincemeat. Russell's biographer John L. Ingham states however that "there is nothing, absolutely nothing, in his R.A.F. record to show that he was anything more than a wireless mechanic and radio operator".

Russell took up writing full-time in the late 1940s. He became an active member of British science fiction fandom and the British representative of the Fortean Society. He won the first annual Hugo Award for Best Short Story in 1955 recognizing his humorous "Allamagoosa" as the year's best science fiction.

The 1962 novel The Great Explosion won a Prometheus Hall of Fame Award in 1985—the third naming of two works to the libertarian science fiction hall of fame. The 1957 novel Wasp has been a finalist for the honor, which is now limited to one work per year.

The Science Fiction and Fantasy Hall of Fame inducted Russell in 2000, its fifth class of two deceased and two living writers.