Fireball XL5 is a 1960s British children's science-fiction puppet television series about the missions of Fireball XL5, a vessel of the World Space Patrol that polices the cosmos in the year 2062. Commanded by Colonel Steve Zodiac, XL5 defends Earth from interstellar threats while encountering a wide variety of alien civilisations.

Inspired by the Space Race, Fireball XL5 was created by the husband-and-wife team of Gerry and Sylvia Anderson and filmed by their production company AP Films (APF) for ITC Entertainment. It was APF's final black-and-white series and the third to be made in what the Andersons dubbed "Supermarionation": a style of production in which the characters were played by electronic marionettes whose mouth movements were synchronised with the voice actors' pre-recorded dialogue. Zodiac was voiced by Paul Maxwell while two of his companions – XL5 co-pilot Robert the Robot and "space doctor" Venus – were voiced by Gerry and Sylvia Anderson themselves. The series' scale model special effects were directed by Derek Meddings.

Filming of Fireball XL5's 39 half-hour episodes began in February 1962 and the series premiered on ATV London (part of the ITV network) on 28 October that year. It was also purchased by NBC in the United States, becoming the only Anderson series to air on an American network. The TV episodes were supplemented by an audio play, comic strips in TV Comic and TV Century 21, and other tie-ins including books, toys and model kits. The series was regularly repeated on British TV until 1974 and has since been released on DVD in the UK, US, Canada and Australia.

In June 2023 The British free-to-air vintage film and nostalgia television channel Talking Pictures TV commenced a rerun of the series on Saturday afternoons.

Regarded by some commentators as a space opera or space Western, Fireball XL5 has been praised for its music; its closing theme – "Fireball", sung by Don Spencer – was commercially released to moderate success in the UK charts. It is often confused with Space Patrol, a puppet series with a similar premise that was made by the Andersons' former collaborators Roberta Leigh and Arthur Provis.