The BAFTA Award for Best Documentary is a film award presented annually by the British Academy of Film and Television Arts (BAFTA) at the British Academy Film Awards. It was formerly known as the Robert Flaherty Documentary Award.

In the following lists, the titles and names in bold with a gold background are the winners and recipients respectively; those not in bold are the nominees. The years given are those in which the films under consideration were released, not the year of the ceremony, which always takes place the following year.

is a British organisation that hosts annual awards shows for film, television, and video games (and formerly also for children's film and television). A theatrical documentary award was presented by the Academy between 1948 and 1990. Documentaries have continued to be honoured with British Academy Television Awards since then and have been eligible in all relevant categories at the Film Awards. In 2012, the Academy re-introduced this category in recognition of the number of high-quality theatrical documentaries released in cinemas in the UK each year.