List of number-one albums of 2018 (Australia)
The ARIA Albums Chart ranks the best-performing albums and extended plays in Australia. Its data, published by the Australian Recording Industry Association, is based collectively on the weekly physical and digital sales of albums and EPs. In 2018, 25 albums have claimed the top spot, including Ed Sheeran's ÷, which spent 21 weeks at number one on the chart in 2017. Nine acts, Geoffrey Gurrumul Yunupingu, J. Cole, Post Malone, Shawn Mendes, Sheppard, Amy Shark, Travis Scott, Twenty One Pilots and Bradley Cooper, achieved their first number-one album in Australia.
Chart history
| Date | Album | Artist | Ref. |
| 1 January | ÷ | Ed Sheeran | |
| 8 January | The Greatest Showman: Original Motion Picture Soundtrack | Various artists | |
| 15 January | The Greatest Showman: Original Motion Picture Soundtrack | Various artists | |
| 22 January | The Greatest Showman: Original Motion Picture Soundtrack | Various artists | |
| 29 January | The Greatest Showman: Original Motion Picture Soundtrack | Various artists | |
| 5 February | The Greatest Showman: Original Motion Picture Soundtrack | Various artists | |
| 12 February | The Greatest Showman: Original Motion Picture Soundtrack | Various artists | |
| 19 February | The Greatest Showman: Original Motion Picture Soundtrack | Various artists | |
| 26 February | The Greatest Showman: Original Motion Picture Soundtrack | Various artists | |
| 5 March | Nation of Two | Vance Joy | |
| 12 March | ÷ | Ed Sheeran | |
| 19 March | ÷ | Ed Sheeran | |
| 26 March | ÷ | Ed Sheeran | |
| 2 April | ÷ | Ed Sheeran | |
| 9 April | ÷ | Ed Sheeran | |
| 16 April | Golden | Kylie Minogue | |
| 23 April | Djarimirri | Geoffrey Gurrumul Yunupingu | |
| 30 April | KOD | J. Cole | |
| 7 May | Beerbongs & Bentleys | Post Malone | |
| 14 May | Reverence | Parkway Drive | |
| 21 May | Tranquility Base Hotel & Casino | Arctic Monkeys | |
| 28 May | Beerbongs & Bentleys | Post Malone | |
| 4 June | Shawn Mendes | Shawn Mendes | |
| 11 June | Ye | Kanye West | |
| 18 June | Watching the Sky | Sheppard | |
| 25 June | Youngblood | 5 Seconds of Summer | |
| 2 July | Pray for the Wicked | Panic! at the Disco | |
| 9 July | Scorpion | Drake | |
| 16 July | Scorpion | Drake | |
| 23 July | Love Monster | Amy Shark | |
| 30 July | Mamma Mia! Here We Go Again: The Movie Soundtrack | Various artists | |
| 6 August | Mamma Mia! Here We Go Again: The Movie Soundtrack | Various artists | |
| 13 August | Astroworld | Travis Scott | |
| 20 August | Scorpion | Drake | |
| 27 August | Sweetener | Ariana Grande | |
| 3 September | Misery | The Amity Affliction | |
| 10 September | Kamikaze | Eminem | |
| 17 September | Kamikaze | Eminem | |
| 24 September | Kamikaze | Eminem | |
| 1 October | Kamikaze | Eminem | |
| 8 October | Home | John Butler Trio | |
| 15 October | Trench | Twenty One Pilots | |
| 22 October | Nature | Paul Kelly | |
| 29 October | A Star Is Born | Lady Gaga and Bradley Cooper | |
| 5 November | A Star Is Born | Lady Gaga and Bradley Cooper | |
| 12 November | A Star Is Born | Lady Gaga and Bradley Cooper | |
| 19 November | A Star Is Born | Lady Gaga and Bradley Cooper | |
| 26 November | A Star Is Born | Lady Gaga and Bradley Cooper | |
| 3 December | A Star Is Born | Lady Gaga and Bradley Cooper | |
| 10 December | A Star Is Born | Lady Gaga and Bradley Cooper | |
| 17 December | A Star Is Born | Lady Gaga and Bradley Cooper | |
| 24 December | A Star Is Born | Lady Gaga and Bradley Cooper | |
| 31 December | A Star Is Born | Lady Gaga and Bradley Cooper |