1980

February

 * 14 - Dr. Owen Harper, Torchwood Three operative, is born. (TW: Exit Wounds, WEB: torchwood.co.uk)

April

 * 15 - Birth of Samantha Jones, future companion of the Eighth Doctor.

December

 * 8 - Knowing of the impending assassination of former member of The Beatles John Lennon, The Doctor, Ace and Bernice Summerfield have traveled to New York City. Mark David Chapman, influenced by the Blue, shoots and kills him anyway. (NA: The Left-Handed Hummingbird)
 * 25 - Professor Edward Travers, CBE, dies. (MA: Downtime)

Unknown dates

 * Victoria Waterfield visits Det-Sen Monastery in Tibet, believing she is following a summons from her father. (MA: Downtime).
 * Sarah Jane Smith claimed to Laurence Scarman that she have come from the year 1980, though this is disputed. (DW: Pyramids of Mars; see UNIT dating controversy).

Negated timeline

 * The Doctor brings Sarah Jane Smith and Laurence Scarman from 1911 and shows them what 1980 would look like if Sutekh had succeeded in freeing himself, a lifeless Earth orbiting a dead sun. This example of alternate time convinces Sarah that they must return to 1911 and stop Sutekh. (DW: Pyramids of Mars)

January

 * 5 - DW: The Horns of Nimon Episode 3 is first broadcast.
 * 12 - DW: The Horns of Nimon Episode 4 is first broadcast, bringing an end to the season six weeks earlier than planned due to the cancellation of DW: Shada. Final episode to feature the original 1960s arrangement by Delia Derbyshire of the Doctor Who theme music, specifically the arrangement introduced in the 1967 serial DW: The Macra Terror. Also final use of the diamond-shaped series logo and Bernard Lodge "tunnel" opening sequence. This episode also brings to a close Graham Williams' involvement as producer and of Douglas Adams as a member of the writing team. Also, this is David Brierley's final televised performance as the voice of K9 (although he also voiced the character for the incomplete Shada).
 * 24 DWN: Doctor Who and the Underworld is first published.
 * American edition of DWN: Doctor Who and the Android Invasion published by Pinnacle Books.

February

 * 4 - Former Script Editor and writer David Whitaker dies in Australia.
 * 21 - DWN: Doctor Who and the Invasion of Time is first published.

March

 * 20 - DWN: Doctor Who and the Stones of Bloodis first published.
 * Target Books reissues the 1976 non-fiction book REF: The Making of Doctor Who.
 * American edition of DWN: Doctor Who and the Seeds of Doom published by Pinnacle Books. This was the last re-print of a Doctor Who novelisation by Pinnacle, and as of 2009 stands as the last American edition of a Doctor Who novel to date.

April

 * 24 - DWN: Doctor Who and the Androids of Tara is first published.

May

 * 26 - DWN: Doctor Who and the Power of Kroll is first published.

June

 * The BBC announces that K9 will be leaving Doctor Who during the next season. According to The Television Companion by David J. Howe and Stephen James Walker, the response to this announcement by fans inspires John Nathan-Turner to pitch the idea of a spin-off series featuring the character, which later became K9 and Company.
 * 4 - Philip Olivier born.
 * 26 - DWN: Doctor Who and the Armageddon Factor is first published. Due to the inability of Target Books to come to an agreement with Douglas Adams, this would ultimately be the last of the Key to Time- arc serials to be novelised. The remaining serial, DW: The Pirate Planet, would not be officially novelised.
 * DWN: Junior Doctor Who and the Brain of Morbius is first published. This is a short version of DWN: Doctor Who and the Brain of Morbius and is the second of two such books released (a paperback edition of DWN: Junior Doctor Who and the Giant Robot is also released in 1980). Reportedly the book was originally to have been released in 1978.
 * Doctor Who Magazine begins publishing Doctor Who-universe comics written by future comics superstar writer Alan Moore.

August

 * Doctor Who Annual 1981 published. Beginning this year the annual, previously published each September, moves to August.
 * 6 - Barry Justice (King Charles IX in DW: The Massacre of St Bartholomew's Eve) dies in London.
 * 7 - Final issue of Doctor Who Weekly, which changes to a monthly magazine in September.
 * 21 - DWN: Doctor Who and the Keys of Marinus and DWN: Doctor Who and the Nightmare of Eden are first published. For the first time in several years, Target Books has released more than one book on the same day.
 * 30 - DW: The Leisure Hive Episode 1 is first broadcast, launching a longer-than-usual Season 18 that is Tom Baker's final season and the first series produced by John Nathan-Turner. Among the numerous changes evident with this episode is the introduction of a radically different arrangement of the Doctor Who theme by Peter Howell and a new neon-tubing style series logo. A modified costume is also introduced for the Doctor. Season 18 will be the last truly "season-long" series, as during the Davison era the show will air from January to March only (two episodes per week), and be subject to an ever-decreasing number of episodes thereafter.

September

 * Doctor Who Magazine begins publishing as a monthly, initially changing its title from Doctor Who Weekly to Doctor Who: A Marvel Monthly.
 * John Nathan-Turner approaches Peter Davison about taking over from Tom Baker as the star of Doctor Who.
 * 6 - DW: The Leisure Hive Episode 2 is first broadcast.
 * 13 - DW: The Leisure Hive Episode 3 is first broadcast.
 * 20 - DW: The Leisure Hive Episode 4 is first broadcast.
 * 27 - DW: Meglos Episode 1 is first broadcast, featuring the return of Jacqueline Hill to Doctor Who, albeit as another character. John Leeson returns as the voice of K9.

October

 * 4 - DW: Meglos Episode 2 is first broadcast.
 * 11 - DW: Meglos Episode 3 is first broadcast.
 * 16 - DWN: Doctor Who and the Horns of Nimon is first published. (Although the series branding has changed to a new logo, the the previous logo is still used by Target Books for several more volumes.
 * 18 - DW: Meglos Episode 4 is first broadcast.
 * 24 - At a press conference, the BBC announces that Tom Baker will be leaving Doctor Who at the end of the current season.
 * 25 - DW: Full Circle Episode 1 is first broadcast, launching what would become known as the E-Space Trilogy. Matthew Waterhouse debuts as new companion Adric.

November

 * The BBC announces that Peter Davison has been cast as the Fifth Doctor.
 * Publication of REF: A Day with a TV Producer, a non-fiction work profiling John Nathan-Turner and the production of DW: The Leisure Hive.
 * 1 - DW: Full Circle Episode 2 is first broadcast.
 * 8 - DW: Full Circle Episode 3 is first broadcast.
 * 13 - DWN: Junior Doctor Who and the Brain of Morbius published in paperback.
 * 15 - DW: Full Circle Episode 4 is first broadcast.
 * 22 - DW: State of Decay Episode 1 is first broadcast.
 * 29 - DW: State of Decay Episode 2 is first broadcast.

December

 * 4 - DWN: Doctor Who and the Monster of Peladon is first published.
 * 6 - DW: State of Decay Episode 3 is first broadcast.
 * 8 - Ex-Beatle John Lennon, who appeared as himself in DW: The Chase, is shot and killed by Mark David Chapman outside his home in New York City.
 * 13 - DW: State of Decay Episode 4 is first broadcast.
 * 30 - Tom Baker and Lalla Ward marry; Baker is in the midst of filming DW: The Keeper of Traken, while Ward's final episodes as Romana have yet to be broadcast.
 * Marvel Premiere issue 57 is published by Marvel Comics in the United States. This comic, featuring Fourth Doctor comic strip reprints from Doctor Who Weekly, is the first American comic ever published based upon the Doctor Who TV series (a previous comic published in the mid-60s by another US publisher was based upon the Dr. Who and the Daleks movie, not the TV series). This comic, and three other issues that follow, lead to the launching of a monthly Doctor Who title by Marvel in 1984.

Unknown dates

 * The Adventures of K9, a children's book series by David Martin, is published by Sparrow Books.
 * Tom Baker and Lalla Ward appear as The Doctor and Romana in a series of commercials for Australian television, advertising Prime Computers (room-sized computer system for business). While most of the commmercials feature them in their standard character roles, the final commercial in the series has Romana flirting with the Doctor and ends with the Doctor proposing marriage to her!