Events
- 13 January – Network Ten introduces with a new logo, which is still in use to this day.
- 14 January – During the Molly's Melodrama segment, Mr Wonderful makes an appearance to receive a massive punch-up with Molly Meldrum (later Red Symons joined in) live on Hey Hey It's Saturday.
- 17 January – Seven Network's long running breakfast program Sunrise makes its first broadcast.
- 10 February – The Simpsons makes it debut on Network Ten at 7:30 pm with the first season episode of "Bart the Genius".
- March – Tony Barber and Alyce Platt announcing they quit Sale of the Century.
- 15 March – Steve Vizard wins the 1991 Gold Logie.
- 16 March – Disgraced Neighbours producers have reported that star Beth Buchanan (sister of ex-Hey Dad star Simone) is going to leave the troubled series when her contract expires in June. As a result of Post-Neighbours, she is keen to travel overseas and is also believed to be planning a movie role.
- 17 March – ABC debuts a new Sunday morning children's wrapper programme called Couch Potato presented by Australian actor Grant Piro.
- April – Glenn Ridge and Jo Bailey replace Tony Barber and Alyce Platt on Sale of the Century.
- 6 April – Network Ten's troubled soap opera Neighbours is set to lose a record number of cast members as many of them have contract renewals coming up. Ian Williams, who plays medical student Adam Willis, is confirmed to be leaving, while co-star Lucinda Cowden who plays Melanie Pearson is also believed to be quitting when their contracts expire.
- 30 April – ABC's live comedy series The Big Gig returns with a new series.
- 13 May – Triple J presenter and radio announcer Michael Tunn takes over as presenter of the Australian weekday magazine series The Afternoon Show.
- 6 April – Network Ten's disgraced soap opera Neighbours is set to lose never more than 25 actors along with 200 crew people, being terminated from their roles as part of the severe revamp. The names were Ian Smith (Harold Bishop), Lucinda Cowden (Melanie Pearson), Stefan Dennis (Paul Robinson), Gillian & Gayle Blakeney (Caroline & Christina Aleesi), Mark Little (Joe Mangel), Kristian Schimid (Todd Landers), Jeremy Angerson (Josh Anderson), Beth Buchanan (Gemma Ramsay), Amelia Frid (Cody Willis), Ben Guerens (Toby Mangel), Miranda Fryer (Sky Bishop) and Ian Williams (Adam Willis). Joining the shamed series will be former Cleo covergirl of the year Rachel Blakely and former models Scott Michaelson and Andrew Williams.
- 15 May – Canadian teen drama series Degrassi High, the third in the Degrassi trilogy series makes its debut on ABC.
- 1 June – Reruns of the classic ABC drama series Patrol Boat are now airing on Network Ten.
- 10 June – British children's animated series Postman Pat and Tugs premiere on ABC for the very first time.
- 24 June – ABC debuts its new children's game show Big Square Eye hosted by ex-Neighbours star Bob La Castra.
- 4 July – British long running soap opera series EastEnders airs on ABC for the very last time due to the show not getting any more episodes from the UK where it originally came from, although it was later repeated on UK TV on cable television.
- 16 July – Australian live comedy series The Big Gig airs its final episode on ABC.
- 19 July – Ron Casey and Normie Rowe receive a massive punch-up live on Midday with Ray Martin. In Neighbours, Harold Bishop has had a massive heart attack in the Coffee Shop.
- 15 August – American talk show The Oprah Winfrey Show makes its debut on Network Ten as a late-night program.
- 7 September – Neighbours star Richard Huggett, who plays Jim Robinson's s half-son Glen Donnelly has told producers that he will not be renewing his contract when it expires in November. He will be seen on air until February 1992.
- 19 September – Network Ten's shamed soap opera Neighbours airs a tragic episode: Joe Mangel proposes to Melanie Pearson announce they will immigrate to the UK, Adam Willis leaves Ramsay Street for Europe, Harold Bishop is murdered off the coast while on holidays with Madge to Tasmania – this was the final episode.
- 25 October – In Neighbours, Joe Mangel, Melanie Pearson and Sky Bishop depart.
- 5 November – The hit long running British science fiction series Doctor Who returns on ABC after a long absence since its last air in mid 1990, starting off with the fourth serial of Season 17 Nightmare of Eden and ending with the seventh and final serial of Season 18 Logopolis in early 1992. A convention of the series is also being held at the local Noah's on the Beach hotel in Newcastle, New South Wales.
- December – The Seven Network wins the 1991 ratings year with a record of 33.8% share for Total People.
- 3 December – American sitcom The Fresh Prince of Bel-Air starring American rapper Will Smith makes it debut on Nine Network.
- 30 December – Australian children's series The Book Place debuts on Seven Network. It will replace Fat Cat and Friends in 1992.
- 31 December – The Northern New South Wales television market is aggregated, with Prime Television taking a Seven Network affiliation, NBN taking a Nine Network affiliation & NRTV (now Southern Cross Ten) taking a Network Ten affiliation.
- Whole year – Hey Hey It's Saturday tours Australia, celebrating the show's 20th Anniversary, touring Adelaide, Perth, Brisbane, including the opening of Warner Bros. Movie World on the Gold Coast and Warner Bros. Studios in Hollywood.
Debuts
Domestic
International
Changes to network affiliation
This is a list of programs which made their premiere on an Australian television network that had previously premiered on another Australian television network. The networks involved in the switch of allegiances are predominantly both free-to-air networks or both subscription television networks. Programs that have their free-to-air/subscription television premiere, after previously premiering on the opposite platform (free-to air to subscription/subscription to free-to air) are not included. In some cases, programs may still air on the original television network. This occurs predominantly with programs shared between subscription television networks.
Domestic
International
Television shows
ABC TV
Seven Network
Nine Network
Network Ten
Ending this year
Magilla Gorilla
