The Adventures of James Bond Junior 003½ is a 1967 James Bond spin-off novel carrying the Glidrose Productions copyright. It was first published in the United Kingdom by the Jonathan Cape publishing company in 1967 and later in 1968 in the United States by Random House. The American edition was retitled 003½: The Adventures of James Bond Junior. The novel was written under the pseudonym R. D. Mascott.

Although the novel is based around a character who is the nephew of James Bond, in Ian Fleming's own novels, Bond in fact was an only child and an orphan.

In 1966 Harry Saltzman announced a television series about a ten-year-old who fought SPECTRE that could have been based on 003½ but nothing became of it. At some other point Bond film producers Saltzman and Broccoli planned to make either a theatrical feature or a TV series based on the 003½ premise. The producers discussed story ideas with several unidentified screenwriters in London.

The Adventures of James Bond Junior 003½ is considered a failed attempt at launching a youth-oriented line of fiction aimed at 8- to 14-year-olds. A moderately successful television series of the same name was launched in 1991, produced by Eon Productions / Danjaq. The success of the show spawned numerous novelisations, a video game, and comic books. Unrelated to 003½, Ian Fleming Publications began publishing a successful youth-oriented line of Young Bond adventures featuring James Bond as a teenager in the 1930s beginning in 2005.

Although an officially licensed spin-off from the James Bond series, its place within the canon of the books—if any—has never been established.